Intertestamental Period Essay Example for Free

Intertestamental Period Essay INTRODUCTION The overarching goal of the Christian church is to model a Kingdom lifestyle and in so doing facilitate a change in the world towards a lifestyle approved of God. That goal is accomplished by (1) being in the world, but not of the world, (2) being one and (3) using Kingdom methodology to achieve God’s objectives. But achieving the goal using that strategy is made difficult when it must be done in the midst of competing lifestyles. Especially when there is a desire to fit in rather than being ‘peculiar’. During the Intertestamental Period, also called the Second Temple Period by some authors, the Jews experienced cultural and environmental pressures which forced them apart and set the stage for the ministry of Jesus. The following is a brief summary of those pressures. 1. The Jews were bounded on all sides by other cultures and this caused them to compromise their life style to fit in with the world giving up any real distinction between a righteous lifestyle and a worldly lifestyle. Bruce stated that â€Å"the Greek way of life was attractive to many, and slowly but surely it continued to make headway among large sections of the population, including even the great priestly families in Jerusalem. This tendency was inimical to the true calling of Israel, and tended to break down the wall of partition between Jews and Gentiles in the wrong way, by blurring the sharp distinction between Israel’s revealed religion and Greek heathenism.† 2. The Jews moved from ‘being one’ to being ‘standalone competing sects’. It is readily observable that this caused infighting and an inward focus that was detrimental to their inherent mission. This problem was highlighted in later years when Jesus said â€Å"Neither pray I for these alone, but for them also which shall believe on me through their word; 21 That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.† 3. The Use of Political Means to Achieve Kingdom Ends Instead of being in the world, but not of the world, the Jews readily became part of the world by entering into the political system of the culture in an attempt to develop some level of security and ensure their prosperity. The use of political maneuvering was used during the entire 400 year period. For the most part it would be impossible to distinguish the political wrangling of the Jews from that of any other self-interest groups of the day. 4. The combining of church and state in the office of High Priest. The High Priest was supposed to monitor and ensure the spiritual welfare of the Jews. However in during the Intertestamental period, governmental authority was vested in that position by the ruling factions. We can observe the same thing in some churches today. We have Pastors who are not only empowered with the spiritual welfare of the church but are also given carte blanche authority over the governance of the church. And balancing those requirements is difficult at best. We must also consider the varying conquest strategies used by the nations that existed around the Jews. The Semitic nations, which included the Assyrians, the Babylonians, the Ammonites, the Moabites and the Esau-ites deported those they conquered to be settled in foreign lands. Additionally, they had a policy of destroying the religion and culture of those they conquered. The Japhetic nations, which included the Medo-Persians, generally sent the conquered back to their homelands and granted some religious and political self-rule. The Hamitic nations, which included the Egyptians, the Canaanites, the Philistines and the Phoenicians, deported those they conquered and destroyed their culture and religion. Several sources were used to conduct this analysis and as can be expected, various divisions and time periods were used. For the purposes of this paper, we will divide the time period into the following divisions and use these associated dates: (1) 722-433 BC Antecedent Events; (2) 559-331 BC Persian and Medo-Persian Rule; (3) 368-323 BC Hellenistic (Greek) Rule; (4) 323-166 BC Ptolemies and Seleucids Rule; (5) 166-63 BC Jewish (Maccabean and Hasmonean) Self-Rule; (6) 63 BC AD 663 Roman (Herod) Rule. It is noted that the Intertestamental or Second Temple Period ended with the destruction of the Second Temple in AD 70. ANTECEDENT EVENTS722-433 BC There are events that took place prior to the Intertestamental Period that must be considered in this analysis. In 722 BC, Sargon the king of Assyria captured the Northern Kingdom (Israel) and deported the higher Jewish classes to Babylon. These deportations created spiritual crises for the Jews. But in addition, a lot of the cultural aspects of being a Jew were destroyed. According to Kostenberger, the monarchy was destroyed and the sanctuary which was the central focus for the Jewish faith was lost. The Jews, who apparently had a penchant for fitting in with foreign cultures found themselves in close proximity to Gentiles. This created moral and ceremonial problems for those living outside of Judea. In 587 BC, the exact same situations occurred when Nebuchadnezzar the king of Babylon captured the Southern Kingdom (Judah), destroying the Temple and Jerusalem. In 583 BC Cyrus, king of the Medo-Persian Empire, came to power and sent the captives home but only fifty thousand returned to rebuild the Temple. It is suggested that an equal number simply stayed in place opting not to return to an uncertain situation. With the goal of rebuilding the Temple, the Jews forbid the Samaritans to participate due to their mixed race heritage. Offended by this, the Samaritans became obstructionists delaying the building and eventually built their own temple further increasing the schism between the Jews and the Samaritans So we enter the Intertestamental Period with the Jews dispersed in several locales, experiencing and in some cases embracing foreign cultures to the detriment of their culture and faith and having been ruled and subjugated for generations. PERSIAN AND MEDO-PERSIAN RULE559-331 BC Historical Developments The Jews were delivered from their previous captivity by the Persians and for the most part were left undisturbed by the Persians. But they had new and enthusiastic rivals among the Samaritans who had not only delayed the building of the Jewish Temple, but had initiated their rival temple on Mount Gerizim, overlooking the ancient city of Shechem. Impacts on the Jews The remnant of Jews that returned was idolatrous and had lost any sense of reverence for the Scriptures. During this period, idolatry was purged from the Jews. They gained a new sense of reverence for the Scriptures. The Jews developed a firm grasp for the concept of monotheism and completed the Temple reaffirming it as the center of worship. HELLENISTIC (GREEK) RULE368-323 BC Historical Developments It can be defended that the Hellenistic (Greek) Rule Period actually started with the rule of Philip. Philip had brought the whole of Greece under his rule, and intended to lead the combined forces of his empire against the Persians. Some view this as a Macedonian event, but Philip had already embraced the Greek culture. One of Philip’s first acts was to have his young son, Alexander trained in Greek culture. However before Philip could complete his military efforts, he was assassinated and it was left to Alexander to complete his plans. Alexander the Great conquered Persia, Babylon, Palestine, Syria, Egypt and western India. Alexander’s Empire did not last long. In 323 he died of a fever at Babylon, before he had completed his thirty-third year. But even before his death, his followers carried the Greek language and culture all over the Eastern Mediterranean and Western Asia. Impacts on the Jews Caught between opposing forces the Jews lost all sense of security once again. They were immediately between two warring factions being pulled in both directions. This may have been one of the times when the Jews felt an overwhelming desire to fit in to avoid destruction. Hellenization, or embracing the Greek culture, was so powerful that from a cultural standpoint, the Greeks conquered Philip, Alexander and even the Romans when they showed up. The conquerors assumed the Greek language and eventually brought about the translation of the Old Testament into Greek (the Septuagint). Doing so also caused a rift between the Jews who were more traditional. PTOLEMIES AND SELEUCIDS RULE323-166 BC Historical Developments Pursuant to his death Alexander’s generals quarreled over who would succeed him. Alexander’s Empire was eventually divided into several parts. Of these parts only two are of any real concern as they had a major impact upon the Jews. These are the Macedonian kingdom of Egypt, with its capital at Alexandria ruled by the Ptolemies, and Macedonian kingdom of Syria with its capital at Antioch ruled by the Seleucids. By 300 B.C. we find two Macedonian dynasties firmly established in these capitals. Palestine lay between these two kingdoms. Impacts on the Jews Hayford indicates that the Jewish faith was seriously undermined by being in close proximity to Hellenism. The Jews started to neglect Jewish religious rites and customs. But this is not to say that the Jewish faith is inherently weaker than Greek culture. For the Jews, adherence to Greek culture was easier and it was simply more acceptable. But it did cause a schism between the Jews. Two sects emerged which included the Hellenizing party, which was pro-Syrian and the Hasidim party, which eventually became the Pharisees. Once again, we see a division among the Jews. JEWISH (MACCABEAN AND HASMONEAN) SELF-RULE166-63 BC Historical Developments As they were pulled in both directions by two Macedonian dynasties, a Jewish revolt erupted. A Syrian official pushed for a heathen sacrifice in the Jewish village of Modein. Led by the priest Mattathias and his sons Judas, Jonathan and Simon this revolt eventually led to Jewish independence. The Jews retook Jerusalem, cleansed the Temple and restored worship starting a period of Jewish self-rule. However, this was a period of self-rule with major factions competing against each other. Impacts on the Jews In addition to the conflicts with the Syrians, the position of high priest took on political overtones with the high priest being chosen not by Aaronite lineage but by political strength. It is even suggested that bribes were being paid to secure the office. This caused further schisms among the Jews strengthening both the Pharisees and the Sadducees. ROMAN (HEROD) RULE63 BC to AD 663 Historical Developments The self-rule of the Jews ended in 63 BC when Pompey took Syria and entered Israel. Under Roman rule Antipater the Idumaean was appointed procurator by Julius Caesar and was later succeeded by his son Herod. Herod was a converted Jew and yet was one of the most heinous leaders the world had ever seen. A summary of his reign would include marrying the Asmonaean princess, Marianne to secure the support of the Maccabeans; murdering Marianne and her two sons at the behest of his mother; executing his mother Alexandra; murdering forty-three members of the Sanhedrin; Hellenizing the country by erecting a Greek theatre in Jerusalem; restoring the Temple to increase his popularity with the Jews; murdering his son Antipater; and finally committing the slaughter of the infants at Bethlehem. Impacts on the Jews These atrocities by Herod led to the development of three other sects developed during this time which included the Zealots, the Herodians and the Essenes. So near the end of the Intertestamental Period, we find the Jews more fractured than ever before, under the rule of a foreign power and turning to some very questionable means in an attempt to bring about God’s ends. MAJOR PROBLEMS AND RESPONSE 1. With the collapse of the Persian Empire, which had a very lenient attitude toward self-identity and religious freedom for those they had conquered, the Jews had to deal with a series of Greek kings who had a strong belief in their cultural superiority. The Jews were bounded on all sides by other cultures the principle of which was the Greek culture. Bruce calls this ‘the progressive Hellenization of Palestinian Judaism’.. The Jews started to compromise their life style to fit in with the world. In so doing, they give up any real distinction between a righteous lifestyle and a worldly lifestyle. The Jews made the decision to assume the Greek culture in whole or in part with some of them totally abandoning the faith. Others developed a sort of bi-faith practice where they embraced some of their Jewish faith as well as some of the Greek culture. This alone put them at odds with some of the more hardline practitioners of the faith. 2. The Jews moved from ‘being one’ to being ‘multiple standalone sects’. The rise of the Jewish sects resulted from the clash between Hellenism and the Jewish religion and culture. Taylor states that the Hellenism elements were dangerous to the purity of the Jewish faith and formed the new temptation to unfaithfulness just as idolatry had been to their forefathers. The Sadducees Under Jewish self-rule the Sadducees emerge as the party closely associated with the leading priestly families. It is thought that their name was derived from the priest Zadok, whose descendants are commended as faithful priests in Ezek. 44:15. The Sadducees observed only the Pentateuch and were the major supporters of the Hasmonean dynasty. As the ruling aristocracy in Jerusalem, they had a vested interest in maintaining the status quo and with pressure from other sects there was a need to align themselves with the non-Jew ruling powers. They held a majority on the Sanhedrin and were allied with the Pharisees in having Jesus crucified. They held to a literal interpretation of the Law, liberal religious views and feared trouble with Rome. The Pharisees The Pharisees were the largest and most influential Jewish sects. They practiced a form of righteousness that observed a complex system of oral traditions in an effort to flesh out the implications of scriptural commends for everyday life. They were dedicated to teaching both the written and the oral Law attaching great importance to traditions. Consequently they practiced ritual prayer, fasting and tithing. They strictly kept the Sabbath and many other rules for everyday life; devised legal loopholes for their convenience. Their main goals were the restoration of religious freedom and the cessation of the connection between politics and the high priesthood. Their popularity among the people increased steadily. Most of the scribes, or popular teachers of the law, belonged to the Pharisaic party. Politically, the Pharisees were the power brokers between the masses and the aristocracy. They were scrupulous about the Law and viewed themselves as separate from those who were lax about keeping it. The Zealots The Zealots were almost a military arm of the faith and were increasingly interested in political freedom. Their means were very aggressive and won the bulk of Jews to their cause They advocated the violent overthrow of Rome, refused to pay taxes and regarded any loyalty to Caesar or Rome a as sin. Their opposition to Jesus may have come from His discourse â€Å"They say unto him, Caesars. Then saith he unto them, Render therefore unto Caesar the things which are Caesars; and unto God the things that are Gods.† The Essenes The Essenes were one of the smaller sects and little is known of their origins. Their solution to the pressure and sects was to completely withdraw from society. They formed a sect that completely lived in seclusion. They turned to a philosophy that said we’re not of the world; neither will we be in the world. The Herodians The Herodians were a sect of influential Jews who were wholly politically minded. They still called themselves Jews but had pretty much left the faith. Even with his long list of atrocities, they completely supported Herod and by implication the Romans. This was their method of surviving when facing the pressures and challenges of the occupation and the various sects around them. 3. The Use of Political Means to Achieve Kingdom Ends The Jews, having lost belief in the ability of their faith to support them in their occupied and factional state turned to the use of secular politics to control their environment. Eventually, they came to pay little attention to the spiritual ideals of Israel. Their chief aim was secular power and aggrandizement. This can only be viewed as completely giving up the idea of being God’s people and in effect just throwing in the towel. 4. The combining of church and state in the office of High Priest. Carroll speaks of the evils involved with combining church and state. First you have religious power and governing power all handed to one individual. This can open to door to the state then having a say in who should receive those powers. Having this much power up for grabs sooner or later will result in the position becoming a matter of barter and sale. CONCLUSION These are major problems facing the Jewish people, but of them all, the greatest has to be the continued fracturing of the people into smaller and smaller self-interest groups. So the greatest threat to the Jewish people during the Intertestamental Period was not the warring factions around them. Not even the heinous actions of a tyrannical leader, but rather their own willingness to cease ‘being one’. There is an African Proverb that states â€Å"when there is no enemy within, the enemy without can do us no harm.† The Jews, in their attempts to meet the challenges around them were doing themselves great harm. But the Intertestamental period is a preface to the coming of Jesus. And it would be difficult to find a better time for the One who would unite all things under Himself. BIBLIOGRAPHY Bruce, F.F. The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 64. Carroll, Benajah Harvey. Between the Testaments, A Class on Biblical History. Southwestern Baptist Theological Seminar, Fort Worth, Texas. 1914. Gene Taylor. 2005. Between the Testaments: A Study of the 400 Years of Biblical Silence and the Relevant Empires. http://www.padfield.com/acrobat/taylor/between.pdf [Accessed July 25, 2013]. Hayford, Jack W. 1995, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study. Nashville: Thomas Nelson Publishers. Kostenbergen, Andreas J., L. Scott Kellum and C. L. Quarles. 2009, The Cradle, The Cross and the Crown. Nashville: BH Publishing Group. [ 1 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 12. [ 2 ]. John 17:20-21 [ 3 ]. Benajah Harvey Carroll. Between the Testaments, A Class on Biblical History. Southwestern Baptist Theological Seminar, Fort Worth, Texas. 1914, 6-8. [ 4 ]. Andreas J. Kostenberger, L. Scott Kellum and C. L. Quarles, The Cradle, The Cross and the Crown, (BH Publishing Group, 2009), 63. [ 5 ]. Benajah Harvey Carroll. Between the Testaments, A Class on Biblical History. Southwestern Baptist Theological Seminar, Fort Worth, Texas. 1914, 6-8. [ 6 ]. Jack W. Hayford, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study Nashville: (Thomas Nelson Publishers, 1995), 507. [ 7 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 10. [ 8 ]. Jack W. Hayford, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study Nashville: (Thomas Nelson Publishers, 1995), 507-508. [ 9 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 10. [ 10 ]. Jack W. Hayford, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study Nashville: (Thomas Nelson Publishers, 1995), 508. [ 11 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 11. [ 12 ]. Jack W. Hayford, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study Nashville: (Thomas Nelson Publishers, 1995), 508. [ 13 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 11. [ 14 ]. Jack W. Hayford, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study Nashville: (Thomas Nelson Publishers, 1995), 509. [ 15 ]. Ibid, 510. [ 16 ]. Ibid, 510. [ 17 ]. Ibid, 511. [ 18 ]. Benajah Harvey Carroll. Between the Testaments, A Class on Biblical History. Southwestern Baptist Theological Seminar, Fort Worth, Texas. 1914, 42-43. [ 19 ]. Jack W. Hayford, Hayford’s Bible Handbook: The Complete Companion for Spirit-Filled Bible Study Nashville: (Thomas Nelson Publishers, 1995), 511. [ 20 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 11. [ 21 ]. Gene Taylor. 2005. Between the Testaments: A Study of the 400 Years of Biblical Silence and the Relevant Empires. http://www.padfield.com/acrobat/taylor/between.pdf [Accessed July 25, 2013], 33. [ 22 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 63. [ 23 ]. Andreas J. Kostenberger, L. Scott Kellum and C. L. Quarles, The Cradle, The Cross and the Crown, (BH Publishing Group, 2009), 72. [ 24 ]. Ibid, 95. [ 25 ]. Gene Taylor. 2005. Between the Testaments: A Study of the 400 Years of Biblical Silence and the Relevant Empires. http://www.padfield.com/acrobat/taylor/between.pdf [Accessed July 25, 2013], 35. [ 26 ]. Ibid, 34. [ 27 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 64. [ 28 ]. Andreas J. Kostenberger, L. Scott Kellum and C. L. Quarles, The Cradle, The Cross and the Crown, (BH Publishing Group, 2009), 72. [ 29 ]. Gene Taylor. 2005. Between the Testaments: A Study of the 400 Years of Biblical Silence and the Relevant Empires. http://www.padfield.com/acrobat/taylor/between.pdf [Accessed July 25, 2013], 35. [ 30 ]. Mt 22:21 [ 31 ]. Gene Taylor. 2005. Between the Testaments: A Study of the 400 Years of Biblical Silence and the Relevant Empires. http://www.padfield.com/acrobat/taylor/between.pdf [Accessed July 25, 2013], 35. [ 32 ]. Ibid, 35. [ 33 ]. F.F. Bruce, The Period Between The Testaments: I, Political Development. Department of Biblical History and Literature in the University of Sheffield, 1949, 64. [ 34 ]. Benajah Harvey Carroll. Between the Testaments, A Class on Biblical History. Southwestern Baptist Theological Seminar, Fort Worth, Texas. 1914, 11.

English Present: Simple And The Present Progressive

English Present: Simple And The Present Progressive Introduction: As a teacher of English to Arabic speaking students I have encountered a number of specific difficulties Arab students have in mastering the English language. In this paper, I would like to focus on a particular grammatical problem they have in the area of verb tenses because, of all the mistakes that my students make, mistakes with verbs and verb tenses impede communication to the greatest degree. The specific problem I will attempt to look at the area of verbs is the problem that Arabic speakers have in using and confusing the present progressive. I will base the evidence for these mistakes on actual writing errors that Arabic students have made. Mistakes such as I am live in Abu Dhabi. come up frequently in my students writing. This paper is basically a contrastive analysis since I feel that the majority of my students problems in this area come from mother tongue interference. However, as will be noted below, this does not mean I rule out other sources of errors such as intralingual errors. The following is the outline of this paper: In the first section of this paper, I will describe the various aspects of the grammatical structure of the present simple and the present progressive in the English language. In the second section of the paper, I will contrast the grammatical structure of the present simple and the present progressive with its Arabic counterparts. I will show how Arabic has structures that vary significantly and radically from their English counterparts. In the third section, I will introduce a number of examples takes from students written work and give an indepth analysis of the possible sources of the errors, mainly with respect to mother tongue interference, but also looking at some possible intralingual sources for these errors as well. Finally, in the last section, I will attempt to suggest a general theoretical approach to dealing with such problems Part One: A grammatical description of the English Present Simple and the Present Progressive: The simple present tense As we already know, the simple present of every verb (with the exception of the verb BE, which I will not be dealing with as a grammatical description since it is not the specific focus of this paper) is identical in every person with the basic unmarked base form of the verb except for the third person forms he, she and it to which we generally add s or es (Quirk 1985, p.98). However, numerous irregularities arise in the spelling and pronunciation of this third person form (Leicester 1998, 12.12)(Thomson 1986, p. 150). Questions are formed by using the auxiliaries do, does, in the present, and did in the past by putting all these before the subject. Negation is formed in the same way using dont (or do not) and doesnt, (or does not) in the present, and didnt (or did not) in the past. These forms go after the subject. In addition, the verb must be changed to the basic form. The simple present is used for statements that are always true, (e.g. The earth revolves around the sun.) (Azar 1989,p.2). The simple present is also used for events, actions or situations which are true in the present period of time and which, for all we know, may continue indefinitely, (e.g. Fatima goes to school at Zayed University.) (Azar 1989, p.2) What we are saying in these expressions is that this is how things stand at the present moment (Huddleston 1984, p.81). A further use of the simple present is for actions that are habitual, things that happen repeatedly, (e.g. We study a lot.) (Alexander 1988, p.163)(Quirke 1985, p.107). Observations and declarations are another use of the present simple, as in the sentence (It says here that there is a new night club opening.)(Alexander 19988, p.163). The present simple can also be used to express the future, especially when we want to express strong certainty, (e.g. When we graduate, we will get jobs.). Swan, Huddleston, Lewis, Thomson and Quirke, et. al. also add eight other functions of the present simple which might come up in other contexts such as: Demonstrations and commentaries (e.g. First, I take a bowl and break two eggs in it, thenà ¢Ã¢â€š ¬Ã‚ ¦..) The structures here comes and there goes, (e.g. here comes your husband.) Promises and oaths (e.g. I promiseà ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦., I swear à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦, He deniesà ¢Ã¢â€š ¬Ã‚ ¦..) Formal correspondence (e.g. We write to advise you.) Instructions (e.g. You go left, turn rightà ¢Ã¢â€š ¬Ã‚ ¦.) Stories (e.g. In act one, Hamlet meets the ghost of his father.), which Huddleston calls the historic present. In expressions of understanding such as hear, see, gather (e.g. I hear youre getting married.) Finally, the simple present can be used in newspaper headlines (e.g. RUSSIANS RAISE OBJECTIONS) Since there are so many instances of when to use the present simple, is there any way to summarize all of these? I concur with Lewis explanation that the present simple: 1-Expresses an event as a total single point in time. 2-Expresses an event as a matter of fact. 3-Expresses an event as immediate rather than remote. The present progressive tense Both the simple and progressive forms usually tell us that an action takes place. But the progressive forms also tell us that an activity is or was, or will be, etc. in progress, or thought of as being in progress. In other words, the present progressive tells us that the speaker sees an action as taking place over a period of time as opposed to a point in time. In addition researchers would add that the speaker sees the period as limited (Lewis 1986; Leech, 1975; Huddleston, 1984; Quirke, 1985). The present progressive tense is formed with the present of be (am/is/are) (which adds aspect and voice), said by Quirke to be the finite verb, plus the ing form (the non-finite form) (Quirke 1985, p. 120). There are no complications with the additional ing form; however the spelling of the ing has some irregularities and needs to be taught to students e.g. write, writing; run, running; begin, beginning; lie, lying). (Alexander 1988; Huddleston 1984; Quirke 1985). Question formation takes place by switching the place of the auxiliary be and the subject. Negation is achieved by inserting not between the subject and the auxiliary or by contracting nt with the auxiliary verb forms (with the exception of the first person singular form am) (Quirke, 1985). In the classroom, the classical reason given for why we use the present progressive is that it shows an uncompleted action in progress at the time of speaking. To emphasise this, we often use adverbials like now, at the moment, just, etc. For example, Hes not home at the moment, hes working. (Quirke 1985). The present progressive can also be used to describe actions which have not been happening for long, or are thought of as being temporary situations, and which are going on around now, e.g. Abdullah is living with his aunt until he can find a place of his own.. A further use of the present progressive is to refer to activities and events planned for the future. We generally use adverbials in such sentences unless the meaning is clear from context, e.g. Were spending next Thursday in Abu Dhabi. (Azar 1989; Huddleston 1984; Quirke 1985). The present progressive can also be used to talk about developing and changing situations, e.g. That child is getting bigger all the time. (Swan 1980). Sometimes the present progressive can be used to talk about feelings, such as I am feeling fine. or My back is hurting me.. The present progressive is used to show repeated actions along with adverbs such as always, constantly, continually, forever, perpetually, and repeatedly, such as He is always helping people.. In this sense it conveys not temporariness, but continuousness. (Leech 1975; Huddleston 1984). The present progressive also is used to show repeated actions that are happening around now, e.g. He is studying a lot of English these days. Why is he going to the library? (Swan 1980). Dynamic versus Stative Verbs in the present simple and the progressive tenses Dynamic/progressive verbs refer to verbs which show actions which are deliberate or voluntary, e.g. Im building a house., or changing situations, e.g. Hes becoming fat.. Dynamic verbs can be used in both the progressive as well as the simple forms e.g. I eat at 5:00 (everyday). as opposed to Im eating now.. Stative verbs (also known as non-progressive verbs) are verbs which indicate a state, condition or experience. Specifically, stative verbs fall into categories such as feelings (like, love), thinking/believing (think, know, realize), wants and preferences (need, want), perception and the senses (smell, see), and being, seeming, having, and owning (seem, look, appear). Stative verbs are generally not used in the progressive forms (Quirke 1985). However some stative verbs can be used in both the present simple and the progressive tenses, which results in a different meaning in each form, e.g. Im thinking of a solution. as opposed to I think he is the best man for the job. or These flowers smell good. as opposed to Latifa is smelling the flowers in the garden.) (Alexander 1988; Azar 1989; Azar 1986; Quirke 1985). The present simple versus the present progressive Swan makes note of a number of areas where students might confuse the present simple with the present continuous. A. We use the simple present to talk about things that are true for the present period of time, or, as was noted above, to say this is how things stand at the present moment for the foreseeable future. However, if the event is temporary and is taking place right now, we use the present progressive. Afrah studies at the Higher Colleges. Afrah is studying her English lesson. B. We use the present progressive to talk about habitual actions if these are happening around the moment of speaking. Fayrouz and Fatima are preparing for the Eid holidays. However, if the habitual action is not closely connected to the moment of speaking, we generally use the present simple. I go to Saudi Arabia once every three years. C. Verbs that refer to physical feelings can sometimes be used in either the simple present or the present progressive. I feel great! or Im feeling great! My head hurts. or My head is hurting. (Swan 1980). PART TWO A grammatical description of the Arabic present simple and the present progressive In this part of the paper, I would like to give readers a very brief background of the Arabic verb system in regard to the simple present and the present progressive. The Arabic verb system is very complicated. However, this does not mean that a teacher has to master the Arabic language before s/he is able to pinpoint errors that may be a result of the interference of Arabic in English. One can study the Arabic language with the goal of simply understanding the structure, rather than with the goal of speaking and writing in the language. Let us first look at the present simple, then the present progressive, and finally the verb to be since all of these grammatical items are specifically relevant to the particular problem at hand. A.The Present Simple In Arabic, the formation of the present simple is radically different from English, since Arabic uses a root system made up of the three most important consonants (though two or four consonant roots do sometimes occur). In Arabic the three basic consonants (the root) stay the same but it is by changes in the vowels, the suffixes and the prefixes that tense and number are indicated. It is vastly more complicated than the way some English verbs change tense by changing vowels, e.g. give, gave. For example, the sentence, he learns could be represented phonetically by ya-droo-soo. The d-r-s is the root, ya is the part that indicates this is a third person singular masculine verb (though this is not the pronoun). The pattern of the vowels and consonants (ya + c1 + c2+ oo + c3 + oo), lets the speaker know that this is the present tense. In contrast, the past could be represented by a different pattern; hence, he learned, dar-ah-sah has the pattern (c1 + ai or ah + c2 + ai or ah + c3 + ah) (and this is just one pattern out of ten!) From a sentence point of view the verb in Arabic is not necessarily treated as the nucleus of a sentence and, in the case of the copula verb BE, can be omitted entirely (as we shall see below). The verb can also be placed at the beginning of the sentence. Like its English counterpart, the present simple tense in Arabic expresses a habitual action. There are other functions, but they are not relevant to this discussion. B.The Present Progressive In general, the present simple form is also used in Arabic to express the idea of a continuous action occurring in the present. Hence, the English sentence He is working now. in Arabic becomes He works now. (represented phonetically by huwwah yaamaloo al eyn.) What is he doing? in Arabic becomes What does he do? (represented phonetically by mehzah yafaaloo al eyn?) Hence, in almost all cases, the present simple form is used to show the idea of continuous action in the present. However, there is a single verb form in Arabic called the ism-ul-fail which is the exact parallel to the idea of continuous action. However, the difference in Arabic is that the ism-ul-fail is used very sparingly compared to English and then only for some very specific verbs of movement, or verbs that indicate changing from one state to another (going up, going in, going down, walking to a place, leaving a place, etc.). Since the ism-ul-fail is radically different in form from the English progressive it is doubtful that any interference in form occurs. C.A Few Points About The Verb BE as a Copula Although BE as a copula is not the focus of this paper, it does deserve mention here for two specific reasons. The first point is that BE in Arabic, when it is the copula in the present tense, is unwritten and unspoken (although this is not true of the copula in the past tense or the future where it is written and spoken). (Kharma, 1989, p. 89). For example, the literal translation of the sentence Ahmed is a student. is Ahmed student.. So it is conceivable that students might leave BE out as a copula OR as the helping verb in the present progressive because it does not exist in the present tense in Arabic (although there are other additional reasons why students might forget to add it to the present progressive as we shall see). The second point is that BE is used so often in English, in so many different kinds of structures, and that it is so irregular, that it might simply add to the confusion of students (Kharma 1989, p. 161). Students who keep on being corrected for leaving out the verb to be when it is necessary, may for example, hypercorrect themselves and start to write it everywhere. Again, we shall explore this issue further below. PART THREE A look at some common written errors made by Arabic speaking students when using the English present simple and present progressive Finding the exact causes of any error can be a difficult and meticulous task. This is partly because there may be multiple reasons as to why students make one particular error and these causes may also overlap at any given time. In addition, it is extremely problematic, even for a native speaker of both Arabic and English, (which I am) to know exactly what is going on linguistically in the mind of a student when s/he makes such an error. However, having said that, even with these obstacles, we can at least make some good hypotheses and lists of possibilities as to why these errors occur with our own students. As a result, we will be able to generate classroom strategies and methods in order to correct and remedy these sorts of mistakes. The following categories of errors are the most common that I have found in students written work with regards to the simple present versus the present progressive. I will look at each category in turn, and offer an analysis of the sources for these types of error. Category One Fatima studies now. Ahmed does his homework now. In these sentences, the intention of the Arabic speaking writer seems to be to convey the meaning of what in English would be a present continuous action, expressed by the present continuous tense. This is clear by the use of the adverb now or in the case of other examples not shown here, from other adverbs or the context of the sentence. In examples one and two, the Arabic speaker seems to be transferring the rules of his native language into English. The Arabic speaker usually uses only the present simple to express events that would be expressed in English by both the present simple and the present continuous. Category Two Mariam cant talk, she eating now. This kind of mistake is a bit more problematic in terms of analysis. It could be that the Arabic speaker, feeling that the full meaning of the action is expressed in the verb with the ing, has decided that the am/are/is forms are redundant and unnecessary. It could also be the case that this mistake is a direct transfer of a particular grammatical form in Arabic. In certain cases Arabic speakers do express the present continuous with a verb and prefix change (called ism-ul-fail), but without the corresponding be form. For example, the literal translation of the sentence Ahmed is running. is Ahmed running. . Category Three Are you knowing the way to Dubai? I am wanting to see my family. In this case, the student has learned the present progressive form, but is over generalizing it to all verbs (or perhaps does not remember or has not been taught the rules for exceptions such as the above). These types of errors could very well be intralingual. This over generalization could also be found in sentences that have the function of explaining, demonstrating teaching or narrating such as: Next I am pouring the oil into the cooking pan. Ali is passing the ball to the goalkeeper. Category Four I am live in Abu Dhabi. We are study English. This category is probably the most difficult to analyze. This is because it is unclear whether the Arabic speaker is making the mistake of adding the additional am/is/are form while trying to use the present tense, or making the mistake of forgetting to use the present participle while trying to use the present progressive tense. That is, did the speaker intend to say I live in Abu Dhabi. and use the extra am form by mistake, or did s/he intend to say I am living in Abu Dhabi. and forget the correct present participle form? Of course, there are other possibilities but these seem like the two most likely. We must obviously look at the context of the paragraph to see if we can get the gist of what the speaker meant. The following is a more detailed analysis of these two possibilities from the standpoint of the students reasoning. 1. If we believe from the context that the student was trying to use the present simple and added the additional am in error, then the following analyses apply: A. The student may be confused by the lack of inflectional endings in English, since Arabic is a highly inflected language, and every personal pronoun has a distinct corresponding inflected verb form. The similarity of the verb forms in I live, you live, etc. may seem very awkward to the Arabic speaker. Hence, they may want to remedy the situation by distinguishing the verb forms in some way by, for example, adding an exceedingly familiar and overused verb form like am, are, or is. B. The student may be over generalising based on what they have learned about the present continuous. That is, they may have learned how to form the present continuous quite easily since there is no mother tongue interference from Arabic, (although they may not have mastered its use). They then may go on to conclude that every verb in the present simple or present continuous in English needs to be preceded by am/is/are. C. Similarly, the student may be hypercorrecting. They may have been corrected so many times for forgetting to use the verb BE in their sentences e.g. Ahmed happy, that they may start to feel that every sentence needs the verb BE. 2. However, if we believe that the student was trying to use the present continuous tense and used the present simple live (instead of the present participle living), then the following analyses apply: A. The student may not have correctly understood how to form the present participle by adding ing to the end of the verb. B. Perhaps students have simply forgotten to add the ing prefix because the structure is so different in their language. This is by no means an exhaustive analysis. However, these are, from my experience and collaboration with other colleagues, both native and non-native speakers, some of the major possibilities. PART FOUR Pedogogical implications of the above research for teaching the present simple and the present progressive to Arabic speaking students From the evidence I have presented here, I believe it is clear that many of the mistakes in using the present simple and the present progressive in form (such as omission of the verb to be in the simple present for Arabic speakers, e.g. I studying), as well as other mistakes in usage (e.g. using the simple present when the present progressive is required) seem to be traceable directly to Arabic mother tongue interference. Based on my analyses, reading and discussion with colleagues, I do feel that in this particular area, teachers of EFL to Arabic speakers must consider mother tongue interference as a major impediment to learning the present tense versus the present progressive. If we know that mother tongue interference is the cause of many errors, what should this imply for our teaching? One thing which I think it does not imply is that we teach English from the point of view of the mother tongue. For example, trying to get students to understand English grammar through word for word translations or using the grammatical structure of Arabic to help students to understand the grammatical structure of English are only useful in certain cases, and then only by someone who is a master of both languages. My experience in reading the research, being bilingual and talking to Arabic speaking students who are at the final stages of their English studies leads me to believe that, at least in the case of Arabic and English, that the two languages are sufficiently different that they are both best looked at in their own respective grammars. Students must be made, not only to think in English, but to understand English grammar in terms of English grammar without constantly switching back and forth to compare it with Arabic. Such practices are ineffective and will cause confusion among students. As Lewis says students should never expect the foreign language to be like their ownà ¢Ã¢â€š ¬Ã‚ ¦..the fact that English has verb forms that contain [be] as an auxiliary does not suggest that other languages ought to have a corresponding formà ¢Ã¢â€š ¬Ã‚ ¦.students should be positively encouraged to explore the foreign language within itself rather than through the expectations they bring from their own. (Lewis, 1986, pp. 164-165). In addition, I should add that intralingual factors can also be at work when students make such errors (in addition to context specific factors like student motivation, teaching style and competence, etc.). For example, on the intralingual side, we know that students of ESL from many different language groups and even children make common mistakes with the verb to be. Therefore, many such mistakes might be intralingual. (Mattar 1989). Hence, when we try to analyse our students errors we should not be prejudiced to any one theory and we should try to be open to looking at all possible sources of errors. What we as teachers should be doing in the classroom is continually collecting research on student errors and student learning styles in order to form hypotheses about why such errors occur and why such one approach worked and another didnt. We should then be trying to test these hypotheses to see if they are true or not, and afterwards share this information w ith other teachers in similar situations. Only then will we be able to understand why students make errors and what is the most effective way to correct them. Cell Membrane: Structure And Function Cell Membrane: Structure And Function A cell is a dynamic and a complex structure surrounded by a membrane known as the plasma membrane. This acts like a barrier between the inside of the cell and the outside resulting in different chemical environments on the two sides. The cell membrane is not restricted to the outer surface but is also present inside surrounding the organelles. These biological membranes have played a crucial role in the evolution from prokaryotes to multicellular eukaryotes. In prokaryotes, there is only one type of membrane present i.e. the plasma membrane but the unicellular eukaryotes have intracellular membranes compartmentalizing its contents into different functional chambers known as organelles. Each organelle though performs its own specific function, they cross-talk with each other via these membranes in order to work as a unit. Further, different cells in multicellular eukaryotes communicate with each other through these membranes. The membrane, therefore serves a dual purpose of both protecting the interior of the cell from its external environment and also provides a communication interface between the cell and its surroundings or other cells. The diverse functions performed by biological membranes can be attributed to the molecular composition and structure of these membranes. Models for Cell Membrane Structure It took almost a century to develop the present accepted model of a cell membrane based on various physiological and biophysical studies. Physiological experiments involving the transport of molecules and ions across the membrane by Overton in 1899 suggested that the membrane is composed of lipid molecules. Later, Langmuir (1917) showed that lipids when spread on water using Langmuir trough form a monomolecular layer on the surface of the water by calculating the area per lipid molecule. The hydrophobic tails of these lipids were bent and protruding out from the surface of the water. When this method for measuring the area per lipid molecule was applied to the lipids extracted from the known amount of erythrocyte membranes, Gorter and Grendel (1925) concluded that the lipids exist as a bilayer and not a monolayer in a membrane giving birth to the lipid- bilayer membrane model. In 1935, Danielli and Davson elaborated on the model based on the studies measuring the surface tension that membranes are made up of phospholipid bilayer sandwiched between two protein layers. Based on optical imaging of membrane morphology using electron microscopy, Robertson argued that the basic structure of all the membranes is same and proposed the Unit Membrane Model in 1959 []. Several other studies [review or book] suggested that the lipid bilayer has fluid-like properties with lipids and proteins floating in it. Studies of proteins present in erythrocytes membrane and that extracted from other membranes led Singer and Nicolson to classify membrane proteins as peripheral and integral proteins; and finally proposing the Fluid Mosaic Model in 1972 []. This is the most accepted model describing the structure of a cell membrane. According to this model, mosaic of protein molecules is embedded within the fluid of lipid bilayer which is supported by the freeze-fracture studies of the plasma membrane (Figure). Composition of Membranes Membrane Lipids The lipid bilayer is only 5 to 10nm thick organized in distinct regions primarily attributed to the hydrophobic effect caused due to the amphipathic nature of these molecules with both polar and the non-polar regions (Figure). The interactions of these regions with the aqueous environment have been studied with various techniques like x-ray reflectometry,[1] neutron scattering[2HYPERLINK http://en.wikipedia.org/wiki/Lipid_bilayer#cite_note-Zaccai1975-1] and nuclear magnetic resonance. In order to exclude the non-polar regions from the aqueous environment, lipid molecules arrange in such a manner so that the hydrophobic tails point inwardly towards each other and the polar head groups are exposed on the outside facing the water. The outermost region on either side of the bilayer is completely hydrated and is typically around 8-9Ã… thick. The hydrophobic core of the bilayer is typically 3-4  nm thick. The intermediate region is partially hydrated and is approximately 3 Ã… thick. These lipid molecules arrange spontaneously naturally or artificially in solution to form structures like micelles and liposomes (Figure). Micelles are monolayer spherical structures formed by lipid molecules in aqueous environment. On the other hand, liposomes are concentric bilayer of fluid-filled vesicles surrounding the water compartment on both the surfaces. The membrane of the animal cells is composed primarily of three major types of lipids: phospholipids, glycolipids and cholesterol with phospholipids being the most abundant (Figure). The polar head groups of these phospholipids contain a phosphate group and either a glycerol (known as phosphoglycerides) or sphingosine. There are four major phospholipids present in the animal cells, three are phosphoglycerides namely phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine; and the fourth sphingomyelin is the only sphingolipid. The heads of glycolipids contain a sphingosine with one (known as cerebroside) or more sugars (known as ganglioside) attached to it. Cholesterol is a sterol molecule with a small hydrophilic hydroxyl group and a rigid ring structure that stabilizes the bilayer. Membrane Proteins The membrane consists of different types of proteins accounting for 25-75% of the mass of the membrane and are categorized based on their interactions with the lipid bilayer (Figure). Moreover, the manner in which a protein is associated with the membrane is indicative of its function. Integral or intrinsic proteins are embedded with in the lipid bilayer. These could be transmembrane proteins spanning the entire length of the bilayer and possess hydrophobic domains which are anchored to hydrophobic lipids and hydrophilic domain interacting with external molecules. They could have only one membrane-spanning (single pass transmembrane proteins, e.g. glycophorin) or multispanning (multi-pass transmembrane proteins, e.g. band3 protein of erythrocyte) segments. The transmembrane segments have helical e.g. bacteriorhodopsin or ÃŽÂ ²- barrel structures. These proteins can be extracted from the phospholipid bilayer only by disrupting the hydrophobic interactions by using detergents like S DS or Triton-X 100. Peripheral or the extrinsic proteins, on the other hand, are loosely bound to the hydrophilic lipid and protein groups on the surface of the membrane by weak ionic interactions. These can be easily removed with high salt or extreme pH without disrupting the phospholipid bilayer. Lipid-anchored proteins are covalently bound to lipid molecule which in turn anchors the protein in the cell membrane. The lipid can be phosphatidylinositol, a fatty acid or a prenyl group. Membrane Carbohydrates Carbohydrate moieties are present on the non-cytoplasmic surface of the membrane covalently attached to either protein or lipid molecules forming glycoproteins or glycolipids. These carbohydrates help in orientation of protein molecules on the cell surface and sorting in cellular compartments. The glycocalyx or the cell coat is the layer of carbohydrates on the cell surface that protects it and participates in the cell-cell interaction. The carbohydrates of the glycolipids of the erythrocytes membrane determine the ABO blood groups in human. Fluidity of Membranes Under physiological conditions, phospholipid molecules in the membrane are in the liquid crystalline state and the molecules are not physically attached to each other so, they can move within the bilayer. These movements could be within a monolayer i.e. rotational and lateral or between two layers i.e. flip-flop. Flip-flop movements are rare and slower compared to the other two as it requires energy for a lipid molecule to traverse from one layer to the other. Besides, some proteins also move in the membrane as concluded from studies based on human-mouse cell hybrids produced by fusion of human and mouse cells [Frye and Michael Edidin in 1970] and FRAP (fluorescence recovery after photobleaching) experiments (Figure). Fluidity in the cell membrane is attributed to its lipid composition. The cis-unsaturated fatty acids with kinks in their hydrocarbon tails and shorter lengths of the tails increase the fluidity by preventing the ordered packing of phospholipids in the bilayer. Cholesterol molecules present in the bilayer affects its fluidity differently at different temperatures because of its rigid ring structure. It reduces the fluidity by decreasing the movement of adjacent phospholipids but at low temperatures, it increases the fluidity by preventing solidification [Alberts]. Fluidity of the membrane allows different molecules like proteins to interact with each other to perform various processes like transport of molecules and cell signalling. Moreover, membrane fluidity is required for various cellular processes like cell movement and cell division. Asymmetry of Membranes The two leaflets, that is, the inner and the outer monolayer portions of the lipid bilayer differ in their physical and chemical properties. This is due to the asymmetric organization of the various components of the membrane. For example, glycolipids and glycoproteins are always present on the non-cytoplasmic surface of the plasma membrane. Membrane regions differ in their lipid composition. The outer leaflet contains predominantly phosphatidylcholine and sphingomyelin whereas, the inner leaflet contains phosphatidylethanolamine and phosphatidylserine. The inner leaflet also consists of phosphatidylinositol which play a key role in the transfer of stimuli from the plasma membrane to the cytoplasm [Cooper]. The membrane proteins also differ in their distribution in the two leaflets. For example, spectrin and ankyrin are present on the inner surface of the erythrocytes membrane forming a fibrillar membrane skeleton. GPI-anchored proteins ar present on the external surface of the membr ane. The asymmetry of the membrane suggested different roles played by the components of the membrane present on the two surfaces (Figure eg intestinal epithelial cell membrane:Tight junction , lateral movements). Lipid Rafts The plasma membrane of eukaryotic cells have specialized regions known as lipid rafts which differ in their composition from the rest of the membrane. These detergent-resistant and heterogeneous microdomains are rich in cholesterol, sphingolipids and certain proteins. Lipids in these rafts are more highly ordered and tightly packed as compared to the rest of the lipid bilayer. Various studies have attributed diverse roles like in transport of cholesterol, endocytosis, signal transduction, intracellular trafficking and neural development and function to these lipid rafts. Caveolae is an example of lipid rafts which are the invaginated domains in the plasma membrane. In caveolae, a protein caveolin is associated with the cholesterol in the lipid raft. It plays roles in membrane internalization and cell signaling. [Pike et al, 2002; Wary et al, 1998; Huang et al, 1999; Rothberg et al, 1992] (Review: Razani Lisanti, 2001. Exp. Cell Research 271: 36-44). Might not in endocytosis [Thompsen et al, 2002] see lipid rafts 4 references Functions of membranes: Membranes act as boundaries between the cell and its environment and are essential for maintaining the integrity of the cell and the various membrane-bound organelles within the cell, regulating the transport of materials into and out of the cell, responding to external and internal stimuli, and cell-to-cell recognition. The proteins present on the inner surface of the plasma membrane provides shape and maintains the integrity of the cell by anchoring the cytoskeleton found underlying the cell membrane in the cytoplasm. The major component of the cytoskeleton of the most well studied erythrocyte membrane is the fibrous protein spectrin. This protein interacts with other peripheral proteins like ankyrin, actin and tropomyosin. Dystophin, a member of the spectrin family is found in the membrane skeleton of muscle cells. The importance of these proteins is suggested by the fact that mutations in dystrophin leads to muscular dystrophy. Regulated transport of materials across the membrane is due to the amphipathic nature of the lipid bilayer. Therefore, the membranes are selectively permeable and the ability of a molecule or ion to traverse the bilayer depends majorly on its polarity and also on the size. Non-polar molecules like O2, N2 and benzene and small polar molecules like H2O, glycerol, urea and CO2 can pass the membrane but large uncharged (e.g. glucose), polar molecules (e.g. sucrose) and ions (e.g. H+, Na+, HCO3, Clà ¢Ã¢â€š ¬Ã¢â‚¬Ëœ) are not able to diffuse easily across membranes. Hence, various mechanisms are required for transport of materials across the membrane, including simple diffusion, facilitated diffusion and active transport for micromolecules and exocytosis and endocytosis for macromolecules. In simple diffusion, substances diffuse down their concentration gradient. In facilitated diffusion, movement of molecules down the concentration gradient is facilitated by channel and carrier proteins (e.g. glucose transporter). On the other hand, active transport requires energy to move solutes against their gradients and can be classified into primary or secondary active transport depending on the source of energy. The primary active transport depends on the hydrolysis of ATP and is of different types: P (e.g. Na+ K+ ATPase, Figure), F and V types and the ATP-binding cassette or ABC transporters. In secondary active transport, specific solute indirectly drives the active transport of another solute and does not involve the hydrolysis of ATP. Secondary active transport may include either symport (e.g. Na+/Glucose transporter) or antiport (Cl ­-/HCO3 exchanger). The macromolecules such as proteins and polysaccharides are transported by endocytosis (from inside the cell to th e outside) and exocytosis (from outside into the cell) (Figure). Cell membrane is also involved in cell-cell communication. Specialized membrane structures like gap junctions in animals and plasmodesmata in plants provide the cytoplasmic continuity between cells. Tight junctions and desmosomes help in attachment of a cell to other cells or the extracellular matrix forming tissues. Membrane also maintains cell potential by creating chemical and electrical gradient. Cell signaling: Signals through chemical messengers (chemical or electrical stimuli) acting on the membrane receptors most of them being proteins. These signals are then transduced in the cell leading to a cascade of events in the cell. Specific for different cells like Gprotein, Tyrosine-kinase receptors Peripheral proteins act as enzymes e.g. and receptors In summary, biological membranes are the complex and dynamic structures composed of variety of proteins embedded in the fluid of the lipid bilayer. The amphipathic nature of the lipid bilayer and the diversity of membrane proteins are responsible for the involvement of biological membranes in large number of cellular processes.

History of Anesthesia Essay -- Biology Medicine

  Ã‚  Ã‚  Ã‚  Ã‚  I will be telling you my short little paper on the History of Anesthesia. I will be telling what some terms mean that will be used in anesthesia history. Also I will be telling a some dates from years before our time on how anesthesia came from and who was there, and what drugs came out.   Ã‚  Ã‚  Ã‚  Ã‚  First I will be starting out with several definition of the term anesthesia. The absence of normal sensitiation, especially to pain, as induced by an anesthetic substance or by hypnosis or as occurs with traumatic or pathophysiologic damage to nerve tissue. Anesthesia induced for medical or surgical purposes may be topical, local, regional, or general and is named for the anesthetic agent used, the method of the procedure followed, or the area or organ anesthetized. The people who are permitted to give anesthesia to a patient is an anesthesiologist or a Certified Registered Nurse Anesthetist (CRNA). (Mosby’s Pocket Dictionary of Medicine, Nursing, and Allied Health) There is also two different ways of describing Anesthesia you could either call it anesthesia or analgesic. In the next couple paragraphs I will be going over ways on how anesthesia would be given to a patient who will be going under a surgery.   Ã‚  Ã‚  Ã‚  Ã‚  General anesthesia is the most common way that anesthesia is given to a patient. The absence of sensation and consciousness as induced by various anesthetic agents, given by inhalation or intravenous injection. Most of the time a general anesthesia is given to the patient through an IV to the patient.   Ã‚  Ã‚  Ã‚  Ã‚  Local anesthesia is another common way of inducing a patient. The administration of a local anesthetic agent into tissues to induce the absence of sensation in a small area of the body. Topical anesthesia is a surface analgesia produced by application of a topical anesthetic in the form of a solution, gel, or ointment to the skin, mucous membrane, or cornea. Regional anesthesia is an anesthesia of an area of the body by injecting a local anesthetic to block a group of sensory nerve fibers. Next one would be a caudal anesthesia which would an injection of an agent into the caudal part of the epidural space through the sacral hiatus to anesthetize sacral and lower lumbar nerve roots. An epidural anesthesia is an injection A type of regional block in which a local  Ã‚  Ã‚  Ã‚  Ã‚  anesthetic is injected into the epidural... ...imetry added to the standards for basic monitoring when it comes to an anesthestized patient. 1992 Desflurane was finally made that it could be used clinically. Desflurane is one the anesthesia drugs that must be heated because it is unsable in room temperature. 1994 Sevoflurane also was passed to be used in a clinically stable medical field. 1995 House of Delegates of the ASA approves Practice Guidelines for Preoperative Transesphageal Echocardiography. 1996 End trial carbon dioxide monitoring added to the standards for basic monitoring. End trial carbon dioxide can also be used as EtCO2. Also in this year the Bispectral Index Monitoring System approved for Clinical use. House of the ASA approves Practice Guidelines for Office Based Anesthesia. Last thing in this year Rapacuronium used clinically and it is also always known as a IV drug. WORK CITIED The American Heritage Dictionary of the English Language, 3rd. Edition. 21 November 1846 Longnecker, David E., Murphy, Frank L. Introduction to Anesthesia. Copyright 1997 Dorsch, Jerry A., Susan E. Understanding Anesthesia Equipment Construction, Care, and Complications (3rd. Edition). Copyright 1993

Can Childhood Asthma be Outgrown? :: Health Respiratory Essays

Can Childhood Asthma be Outgrown? Today asthma is the most common chronic childhood disease, with the number of children with asthma increasing every year. In 1995, the Environmental Protection Agency reported that 5.5 million children in the United States had asthma. Now an estimated 6.1 million children under 18 in the United States currently suffer from asthma, according to the American Lung Association. However, some asthma sufferers manage to â€Å"out-grow† their childhood asthma. â€Å"By the time high school was over I found that I wouldn’t need to use my inhaler anymore and I haven’t used my inhaler in about three years,† said Jen Nelson, sophomore journalism major at Northeastern University. Today Nelson is asthma-free and in good health. â€Å"I have been pretty much okay. Last year I got the flu so I had a couple of symptoms, but it wasn’t to the point where I needed to use my inhaler,† said Nelson. At the age of 7, Nelson suffered a â€Å"really bad† asthma attack and was diagnosed with one type of asthma, bronchial asthma. â€Å"I developed it [asthma] because I had so many cases of bronchitis†, said Nelson. After having asthma for about 10 years, Nelson was told by her doctor that her asthma â€Å"wasn’t severe anymore† and â€Å"that they no longer considered her to be asthmatic.† Then there are the asthma patients who still have occasional problems with asthma accompanied with allergies that developed during their childhood. â€Å"I was diagnosed with asthma at a very early age. I have had it ever since I was very little. It has come and gone (and come again) over the years,† said Joanna Old, senior journalism major at Northeastern University. Through the age of 10, Old suffered from severe asthma. â€Å"I was hospitalized when I was around 4 or 5 for asthma†¦[Usually] when you have an asthma attack, your lungs get tight and you hear wheezing. Well, during this particular attack, the nurse didn’t even know what was wrong-it turns out my lungs were closed so tightly, there was no wheezing-no breathing at all. I stayed in the hospital for about 3 or 4 days hooked to an IV with an oxygen tent,† said Old. During this time, Old was also on steroids and used an inhaler regularly to manage her asthma. â€Å"I was actually very sickly looking because of the drugs. I remember my hair being very thin and wispy—and I never wanted to brush it!,† said Old. As Old grew up, her asthma seemed to become less severe.

Study On Biomass Power Plant Environmental Sciences Essay

Power coevals from biomass stuff is going one of the most promising options to the established power workss based on fossil fuels such as coal or natural gas. Biomass Ok, so, biomass is defined as any organic stuff derived from workss, that is available on a renewable footing. These stuffs are by and large known as biomass feedstocks and include: Wood: from forestry fixingss ( foristri – the scientific discipline of caring for woods, and the trees and other workss that grow in them ) or from wood treating systems ( production of wood merchandises, such as mush and paper, building stuffs ) . Energy harvests which are harvests grown specifically for energy applications. Agricultural residues ( residius ) residues from agribusiness reaping or processing. Municipal Waste ( miunicipal ) which is residential, commercial, and institutional post-consumer waste such as waste paper, composition board, nutrient waste. And besides Animal Waste from farms and animal-processing industries. The production of electricity from biomass is described as a C impersonal engineering because when a new works is turning, it absorbs carbon dioxide from the ambiance to make glUcose utilizing energy from the Sun. When this works stuff is burned or decomposed by microorganisms the carbon dioxide is released back to the ambiance. These procedure is known as C rhythm which maintain the atmospheric CO2 degrees and has happened since there have been workss on Earth. Fossil fuels such as coal and gas are besides derived from biological stuff ; nevertheless this stuff absorbed CO2 from the atmosphere many 1000000s of old ages ago and when the dodo fuels are burned, this carbon dioxide is released to the ambiance increasing the natural atmospheric concentrations. The critical difference between biomass and fossil fuels is one of clip graduated table. There are presently two chief procedures used in power workss for the production of electricity from biomass: and they are direct burning and gasification. Direct burning is basically the incineration of dry biomass in the presence of air to bring forth heat. Gasification is a thermochemical transmutation of biomass at high temperature ( 700A °C to 1000A °C ) in the presence of a limited sum of O into a combustible gas which is called syngas and is a mixture composed of chiefly carbon monoxide ( CO ) and H ( H2 ) – C monoxide, H, C dioxide and methane. Now let ‘s see how these procedures are integrated into the biomass power workss. So in the first procedure: The heat produced by direct biomass burning in a boiler can be used to bring forth electricity utilizing a steam turbine in the same manner as in a coal-burning power works. This is a diagram of a typical biomass steam power works. The biomass is collected and taken to the power station. At the power station the biomass is fed into the boiler where it is burned. The heat from firing the biomass is used to boil H2O which generates steam that turns the turbines. The turbines are connected to generators. The generator spins and the mechanical energy is converted to electrical energy. Biomass is renewable as it is a C impersonal beginning of energy. When a works is designed for working merely with biomass it is called dedicated biomass power workss. However, biomass can be burned with coal in bing coal power workss. These are called co-firing workss and are one of the most cost-efficient agencies of change overing biomass to electricity at big graduated table. This method makes usage of the bing substructure of the coal works and therefore it reduces the entire investing. The different co-combustion design constructs are shown in this figure. Co-firing can be direct, with biomass and coal being fed into the same boiler, or indirect, where a pre-treatment like gasification is carried out prior to the burning in the chief unit. In parallel burning, biomass and coal burning are separate and the boilers are connected merely on the steam side. Presently most biomass electricity coevals is based on burning. The graduated table of operation is a really of import factor for the efficiency. The efficiency tends to be in the scope of 18 % to 33 % in systems bring forthing from 10 to 50 MW. The maximal efficiencies could make about 45 % in big graduated table workss bring forthing more than 100 MW. In co-firing workss, efficiency of 39 % can be reached. Now let ‘s speak about gasification in biomass power workss. A typical diagram of a biomass gasification procedure combined with power coevals is shown in this figure. In this illustration, biomass is first dried and so injected into the gasifier. The ensuing biogas is purified in a cleansing system. The purified biogas is so utilized in the conventional Combined – Cycle Gas Turbine ( CCGT ) power works, to bring forth electricity. The biogas produced in the gasification procedure can besides be used in burning engines ( 10 kilowatt to 10 MW ) with efficiency of 30 % -35 % . At larger graduated tables ( & gt ; 30 MW ) , where gasification-based systems are coupled with combined gas and steam turbines the efficiency increases up to about 45 % . There are two others procedures which can be used to bring forth electricity from biomass but they are still in a pre-commercial phase. The first of them is Pyrolysis which is a thermochemical decomposition of organic stuff at high temperatures 325A °C to 500A °C in the absence of O, bring forthing gas and liquid merchandises that could be used in power coevals units or upgraded to transport fuel. This procedure besides produces a carbon-rich residue called biochar and one of the of import facets of biochar is that it is a natural fertilizer that can be used to better dirts quality, which can potentially increase energy harvest productiveness. The 2nd one, anaerobiotic digestion is a natural biochemical procedure in which microorganisms interrupt down the organic stuff, in the absence of air, to bring forth biogas ( chiefly a mixture of around 60 % methane and 40 % C dioxide ) . Anaerobic digestion is a procedure suitable for utilizing wet biomass, organic waste or carnal waste to bring forth power coevals on site. There are a figure of engineerings that support the transition paths of biomass feedstocks into energy. Drying is the most important because High wet content needs to be reduced to increase the net calorific value of the biomass, besides to cut down conveyance costs, and to better burning efficiency and the overall economic sciences of the procedure. Biomass such as agricultural and forest residues can be left in tonss on the harvest home site for deceasing, but particularly in humid climes, or parts with heavy snow autumn, this will non be sufficient to acquire to really low ( & lt ; 20 % ) wet content. Covering biomass hemorrhoids with rainproof sheets is a common step that helps accomplish low wet content and avoids decay of the biomass. In some instances, biomass feedstocks need to be actively dried before transition into utile energy. This can be executable from an economic and environmental point of position if waste heat is used, but to utilize fossil energy for drying biomass is questionable from both an economic every bit good as sustainability point of position. Pelletisation and briquetting Both pelletisation and briquetting are commercially available engineerings to automatically compact biomass. Low quality wood is the major feedstock for production of wood pellets, whereas briquetting is normally used to distill agricultural residues. Pellets are frequently used for long-haul conveyance of fuels for big graduated table usage, for illustration for co-firing in coal discharged power coevals workss. Cleaning The gas obtained from gasification contains drosss and particulates that need to be removed before utilizing it in power workss, because these contaminations can lend to eroding, corrosion, and loss of strength in the gas turbine constituents. Conventional methods for taking contaminations from biogas typically rely on chemical or physical cleansing processes runing at temperatures of 38A °C or less. When cooled to this degree, about all of the steam nowadays in the syngas condenses and the contaminations are removed. But so the gas has to be reheated. So, this procedure is non effectual for gas power workss and that ‘s why there is another engineering that is comparatively new and is called Hot gas killing where the cleansing procedure is carried out at high temperature, so that cut down this efficiency loss and better the gasification works ‘s commercial viability. The disadvantages of the hot gas killing engineering are that operational experience is limited, it has higher costs, and it adds complexness to the procedure ; nevertheless, it is considered to be the technologically more advanced pick for new dedicated biomass workss. BECSS CCS engineering is chiefly discussed in the context of avoiding CO2 emanations from dodo fuels, but the this could besides be used in bioenergy transition workss. The thought behind bioenergy with CCS ( BECCS ) is that capturing and hive awaying the CO2 emitted during bioenergy coevals provides the possibility to take â€Å" impersonal † Carbon dioxide from the ambiance, therefore supplying negative emanations. CO2 impersonal procedure Clean and dependable power beginning if sufficient biomass is available Way to dispose waste stuffs that otherwise would make environmental hazards. Social and economic impacts are besides of import factors in the overall impact of bioenergy production. Bioenergy deployment has considerable possible to make employment in the agricultural and forestry sector and along the supply concatenation, and therefore to profit rural communities. This facet is peculiarly of import in developing states, where much of the population depends on agribusiness for their support. In these states, bioenergy frequently provides energy in rural countries, and there is considerable possible to heighten this function by bettering the efficiency of bioenergy usage and making new, sustainable supply systems for biomass feedstocks. Main barriers confronting enlargement of biomass for power coevals are high costs, low transition efficiency and feedstock handiness. As any new engineering, biomass power coevals requires presently in most instances some degree of fiscal support. In the long term, bio-power potency will depend on engineering progresss and on competition for feedstock usage, and with nutrient production for cultivable land usage. Long-distance transit reduces economic and environmental attraction of biomass. Hazards associated with extended usage of biomass relate to intensive agriculture, fertilisers and chemicals use and biodiversity preservation. Certifications that biomass feedstock is produced in a sustainable manner are needed to better credence of public wood and lands direction. The usage of energy from biomass day of the months back to the first clip a fire was lit from the burning of wood. Prior to the industrial revolution, biomass was used for all of our energy demands. Up until the 1880s wood was used for 91 % of all our energy requirements.A 1890. Coal began to displace wood used in steam coevals. 1980s. High oil monetary values and dependance created new involvement in biomass energy, biomass power workss were built in North America and a big biomass power industry rapidly developed in California. By 1985, California had 850 megawatts of installed biomass power capacity. 1990s. Governments take a greater involvement in utilizing renewable energy, such as biomass, to diminish nursery gases and other emanations. 2000. A study of 133 states by the International Energy Agency shows that the biomass portion of entire energy ingestion is 10.5 % Presently, bioenergy electricity is chiefly generated through steam power coevals, including co-firing workss. Electricity supply from biomass has been increasing bit by bit since 2000 and in 2010 biomass provided around ( 280 TWh ) 1.5 % of universe electricity production. Power coevals from biomass is still concentrated in developed states, but for illustration China and Brazil are besides going of import electricity manufacturers in peculiar from agricultural residues thanks to back up programmes. The theoretical accounts established in these states could besides go a feasible manner to advance bioenergy electricity coevals in other non-OECD states with similar conditions.†¦Harmonizing to the International Energy Agency roadmap, universe bioenergy electricity coevals will increase by more than 10 times from around 290 TWh in 2009 to 3100 TWh in 2050 and could supply around 7.5 % of universe electricity coevals, compared to 1.5 % today. The usage of biomass for power coevals v aries between parts, depending on biomass handiness, transition costs, and the handiness of alternate low-carbon energy beginnings. China histories for the largest portion ( 920 T Wh ) of entire bioenergy electricity coevals in 2050, followed by OECD Americas ( 520 T Wh ) . Other parts besides have considerable coevals degree in 2050 such as OECD Europe ( 370 T Wh ) , Other Developing Asia ( 570 T Wh, of which 250 TWh in India ) , Eastern Europe and former Soviet Union ( FSU ) ( 280 TWh, of which 170 TWh in Russia ) and Central and South America ( 240 T Wh, of which 190 TWh in Brazil ) , some ( e.g. Eastern Europe and FSU, China ) get downing from a really low footing.†¦

Rome’s Decline

Test Essay October 3, 2012 Question: â€Å"What were the main factors in Rome’s decline? Which do you judge as the most important? Why? † When we hear the word â€Å"Rome,† a very definite picture comes to mind. We see a strong military conquering a vast majority of the ancient Mediterranean world, Julius Caesar sitting on his throne, leading Rome to newer heights each day, and the highest, most innovative new technology being put to use as Rome grows stronger and stronger. Rome was a very successful civilization, as it lasted from 100 BC to 476 AD.For a 200 year span, called the Pax Romana, trade, entertainment, the economy, and overall satisfaction increased. This was a time of peace. Unfortunately, because of numerous misfortunes such as power struggles, inflation, military rebellions, and foreign invasions, even the mighty Roman civilization came to an end. Power struggle was a major conflict of Rome. After the Pax Romana, whose last king was Marcus Aurelius, emperors were continuously overthrown and killed.This was such an issue, that during one fifty year period, 26 emperors ruled and either resigned or were murdered. Out of those 26, only one died of a natural death. Because of the constant change of rulers, the kings lost the support of the citizens, since the emperors they were loyal to did not remain in power. The collapse in politics was the first step to the fall of Rome. The economic decline was the second step to the fall of Rome. Large taxes were put in place to support and fund the military due to corruptness.Because of this, a heavy burden was placed upon businessmen and farmers. With the majority of their income going to the large taxes, farmers were financially struggling. They could no longer afford their land, so they were forced to leave and work for large landowners. Money gradually started losing its value, and inflation occurred. The third step in the Roman decline was the military rebellions. Because of the constan t change in emperors, different groups in the military felt loyal to different rulers.This caused the military split and often rebel against each other. The military became so weakened and disorderly that emperors began to hire mercenaries. The final step in Rome’s decline was the foreign invasions from Germanic Tribes. Great Britain, Spain, and France were the first of the Roman territories to be surrendered. Rome itself was shortly after, and it was apparent that the largest and most powerful empire in the world at the time had come to an end. Rome was no more.

Spanish Indefinite Determiners

When they come before nouns, words such as some and any part of a vaguely defined class of words known as indefinite determiners. (A determiner is often classified as a type of adjective.) Such determiners usually function much the same in Spanish as they do in English, coming before the nouns they refer to. More precisely, indefinite determiners are defined as nondescriptive words that refer to, or specify the quantity of, nouns without a specific identity. How Indefinite Determiners Are Used in Spanish Like most other adjectives and determiners, in Spanish the indefinite determiners match the nouns they refer to in both number and gender. The one exception is cada, meaning each or every, which is invariable, keeping the same form whether the accompanying noun is singular or plural, masculine or feminine. Again with the exception of cada, which is always a determiner, the indefinite determiners sometimes function as pronouns. For example, while ninguna persona is the equivalent of no person, ninguno standing alone is a pronoun typically translated as nobody. List of Common Indefinite Determiners Here are the most common indefinite adjectives along with their common translations and sample sentences: Algà ºn, Alguna, Algunos, Algunas The base form of alguno, typically meaning some or one (although not as a number), is shortened to algà ºn with it precedes a singular masculine noun through apocopation and thus is listed that way here. The equivalent pronoun, usually translated as someone, retains the form of alguno. In plural form, the translation some is usually used. Algà ºn dà ­a voy a Espaà ±a. (One day, Im going to Spain.)Tiene algunos libros. (He has some books.)Algunas canciones ya no està ¡n disponibles. (Some songs still arent available.) Cada Cada can be translated as either of the synonyms each or every. A common phrase, cada uno, abbreviated as c/u, is used for apiece. Cada dà ­a voy a la oficina. (I go to the office every day.)Tenemos un libro por cada tres estudiantes. (We have one book for every three students.)Puedes comprar boletos por 25 pesos cada uno. (You can buy tickets for 25 pesos apiece.) Cierto, Cierta, Ciertos, Ciertas Although the singular cierto and cierta translates the English a certain, they are not preceded by un or una. In plural form, they are the equivalent of certain as an determiner. Quiero comprar cierto libro. (I want to buy a certain book.)El problema ocurre cuando cierta persona me cree. (The problem happens when a certain person believes me.)Ciertas estudiantes fueron a la biblioteca. (Certain students went to the library.) Cierto and its variations can also be used as a regular adjective after nouns. It then typically means true or accurate. Estar cierto is used for to be certain.) Cualquier, Cualquiera Translations for cualquier and cualquiera before a noun include any, whatever, whichever, whoever, and whomever. Cualquier estudiante puede aprobar el examen. (Any student can pass the test.)Estudia a cualquier hora. (He studies at whatever time.) As a pronoun, cualquiera is used for either masculine or feminine: Prefiero cualquiera de ellos a Pedro. (I prefer whichever one of them to Pedro.) A plural form, cualesquiera, which is both masculine and feminine, exists but is seldom used. When cualquiera is used after the noun, it emphasizes that the specific identity of the noun is unimportant, somewhat like any old in English: Podemos viajar a una ciudad cualquiera. (We can travel to any old city.) Ningà ºn, Ninguna Ningà ºn and ninguna, meaning no or not any, can be thought of as the opposite of alguno and its forms. Although these words are singular, a plural is often used in translation to English. No quiero ningà ºn libro. (I dont want any books. Note how Spanish requires a double negative here.)Ninguna mujer puede salir. (No women can leave.) The plural forms, ningunos and ningunas, exist but are seldom used. Otro, Otra, Otros, Otras Otra and its other forms almost always mean other. A common mistake of Spanish students is to copy another by preceding otro or otra with un or una, but no un or una is needed. Quiero otro là ¡piz. (I want another pencil.)Otra persona lo harà ­a. (Another person would do it.)Quiero comprar los otros libros. (I want to buy the other books.) Todo, Toda, Todos, Todas Todo and its related forms are the equivalent of each, every, all, or all of. Todo estudiante conoce al seà ±or Smith. (Every student knows Mr. Smith.)Corrieron a toda velocidad. (They ran at full speed.)Todos los estudiantes conocen al seà ±or Smith. (All of the students know Mr. Smith.)Durmià ³ toda la noche. (She slept all night.) Varios, Varias When placed before a noun, varios and varias mean several or a few. Comprà ³ varios libros. (She bought several books.)Hay varias soluciones. (There are several solutions.) As a regular adjective after the noun, varios/varias can mean varied, different or various.) Translating ‘Any’ to Spanish Note that some of these determiners can be translated as any. However, it also is common that when an English sentence is translated to Spanish, no equivalent of any is needed.  ¿Tienen ustedes libros? (Do you have any books?)No tenemos dificultades. (We arent having any difficulties.) Key Takeaways A determiner a type of adjective placed before a noun to indicate that the noun doesnt refer to a specific person or thing.Most Spanish determiners are variable for number and gender.Most of the Spanish determiners can also function as pronouns.

Horned Gopher (Ceratogaulus) - Facts and Figures

Name: Horned Gopher; also known as Ceratogaulus (Greek for horned marten); pronounced seh-RAT-oh-GALL-us Habitat: Woodlands of North America Historical Epoch: Late Miocene (10-5 million years ago) Size and Weight: About one foot long and a few pounds Diet: Plants Distinguishing Characteristics: Large head with small, beady eyes; paired horns on snout About the Horned Gopher (Ceratogaulus) One of the most improbable megafauna mammals of Miocene North America, the Horned Gopher (genus name Ceratogaulus) certainly lived up to its name: this foot-long, otherwise inoffensive gopher-like creature sported a pair of sharp horns on its snout, the only rodent ever known to have evolved such an elaborate head display. To judge by its small eyes and mole-like, long-clawed front hands, Ceratogaulus evaded the predators of its North American habitat and avoided the noonday heat by burrowing into the ground--a trait shared by the prehistoric armadillo Peltephilus, the only other known horned, burrowing mammal in the fossil record. (The Horned Gopher also bears an uncanny resemblance to the mythical Jackalope, which, however, seems to have been made up out of whole cloth sometime in the 1930s.) The big question, of course, is: why did the Horned Gopher evolve horns? An amazing amount of paperwork has been expended on this mystery, the most likely answer coming to us via the process of elimination. Since both male and female Horned Gophers possessed horns of roughly the same size, these horns clearly couldnt have been a sexually selected characteristic--that is, males didnt impress females during mating season with their long horns--and the structures were oriented in such a way that they would have been of practically no use in digging. The only logical conclusion is that these horns were intended to intimidate predators; a hungry Amphicyon, for instance, might have thought twice about lunching on the bite-sized Ceratogaulus (and getting a mouthful of painful horn in the process) if a more easily swallowed creature happened to be cowering nearby.