100% (1)
Pages:
1 pages/≈275 words
Sources:
1
Style:
APA
Subject:
Life Sciences
Type:
Essay
Language:
English (U.S.)
Document:
MS Word
Date:
Total cost:
$ 3.96
Topic:

EVOLUTION M2D2

Essay Instructions:
Sickle cell anemia is a hereditary disorder that primarily affects people of African ancestry, but also other ethnic groups, including people of Mediterranean and Middle Eastern descent. Sickle cell disease is the most common inherited blood disorder in the United States with more than 70,000 Americans affected; 1 in 500 African Americans (NIH, 2007). Furthermore, 1 in 12 African Americans carry an allele for the sickle cell trait, but do not have the disease itself (NIH, 2007). Sickle cell anemia is determined by a single gene and occurs when a person inherits two abnormal alleles (one from each parent), causing a change in the hemoglobin molecule found in red blood cells. Hemoglobin is the molecule in red blood cells that carries oxygen throughout the body. People afflicted with sickle cell anemia have atypical hemoglobin that distorts that shape of red blood cells, changing them from round to crescent- (or sickle-) shaped, which is how the disease got its name. In this activity we will study the incidence of hemoglobin alleles and malaria using a simplified population genetics model. Our population genetics model will focus on a single gene for hemoglobin and its two alleles that code for normal hemoglobin and the allele that codes for the sickle cell trait. You will explore three versions of this population genetics model. The first scenario models the how the frequency of this gene might change from one generation to the next in the absence of natural selection. The last two versions model the behavior of the hemoglobin gene in response to natural selection. You will complete the exercises outlined in the attached document and submit your answers to the accompanying questions in the appropriate discussion board. Please see the attached document for an introduction to the activity. Genetics of Sickle Cell References NIH. (2007). Sickle Cell Disease. Retrieved from http://ghr(dot)nlm(dot)nih(dot)gov/condition/sickle-cell-disease. Instructions to Learners: Worksheet—Conduct the experiments described in "Genetics of Sickle Cell" and fill in the tables provided using the data collected, respond to the questions associated with each experiment (Natural Selection I - US and Natural Selection II - Africa) and submit your completed worksheet in the appropriate dropbox. Please compose a summary of your answers and post the summary to the discussion board. Summary Questions—Please develop clear and concise answers to these questions for use in the Module 3 discussion, "The Genetics of Sickle Cell Anemia Part 2" These responses will be posted to the Discussion Board and shared with the class and evaluated by the instructor. Post your response to the Summary Questions by creating a ‘comment' and submitting your response. You must also read other student's responses and respond to at least two with a clear and thoughtful follow-up explaining whether you agree or disagree, supporting your responses with evidence from your readings or other credible sources. Please include in-text citations and bibliographic information for all sources other than your textbook. PLEASE COMPLETE THE WORKSHEET AND SUMMARY QUESTION
Essay Sample Content Preview:
SICKLE CELL ANAEMIA STUDY Name Institution Affiliation Course Date of Submission Sickle Cell Anaemia Study Table 1 f(HnHn) f(HnSn) f(HsHs) f(Hn) f(Hs) Original geneation 7.5 2.5 0 8.0 2.0 Offspring generation 17.5 2.5 0 10 0 Summary answers on table 1. 1. The frequency of the common allele increased 2. The frequency of the rare allele decreased. 3. The frequencies were the same. 4. Allele frequency of normal haemoglobin increases as the frequency of the abnormal haemoglobin decreases. Table 2; Natural Selection I ( UNITED STATES) f(HnHn) f(HnHs) f(HsHs) f(Hn) f(Hs) Original Generation Before Selection 32 8 0 8.0 2.0 After Selection 32 6 0 8.4 1.6 1st offspring generation Before Selection 1411 537.6 51.2 8.4 1.6 After Selection 1411 376 10 7.9 2.1 2st offspring generation Before Selection 1248 663 88 7.9 2.1 After Selection 1248 464 17 7.8 2.7 3rd offspring generation Before Selection 1248 325 146 7.8 2.7 After Selection 1217 842 29 6 4 Answers to questions on table 2 1. With natural selection, frequencies of the two alleles changed 2. Frequencies of normal alleles reduced while those of abnormal ones increased with natural selection. 3. If natural selection stopped working, the abnormal alleles frequency will reduce and eventually die while those of normal ones will increase. Table 3: Natural Selection II ( AFRICA) f(HnHn) f(HnHs) f(HsHs) f(Hn) f(Hs) Original Generation Before Selection 32 8 0 8.0 2.0 After Selection 29 8 0 7.8 2.1 1st offspring generation Before Selection 1217 655 88 7.8 2.1 After Selection ...
Updated on
Get the Whole Paper!
Not exactly what you need?
Do you need a custom essay? Order right now:
Sign In
Not register? Register Now!