| Biology 100/101 Take-home Assignment #2 Fall 2009 (20 Points) Due At Lecture Monday September 21 |
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Please TYPE your answers on separate paper and attach this sheet as a cover sheet. Drawings may be neatly hand rendered. Read and sign the academic integrity statement below.
NOTE: We encourage people to work and study together, but the final product should be an INDIVIDUAL effort. Discuss and talk over questions together, but write up your answers by yourself after the study session. When you use diagrams or concept maps, create your own rather copying those from the text or lecture materials. Definitions and explanations should be in your words and not those of the textbook author or any other source.
Your job is to convince your instructor that YOU understand these ideas.
Work copied from others will not be accepted. Because answers will be posted on the web immediately after the due time, late work will not be accepted.
Academic Integrity in Biology 100/101
I have read and understand Part #4 of the University of Illinois Student Code, which deals with Academic Integrity.
Signature
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Please use the "Talk to Ed" Forum in Moodle if you wish to discuss the assignment further.
Answers will be linked to the Take-Home Assignment web page shortly after this assignment is due.
Don't overlook the links to web resources and references to lecture outlines below that might be useful in answering these questions. Activities in lecture, discussion, and laboratory classes will also address these questions.
These questions will help you achieve Objectives #3 & 4 for lecture #6.
The diagrams you are asked to produce below are to be your own. DO NOT copy a diagram from the text, the web, or any other source. Your drawings do not need to be beautiful, but they do need to be neat and understandable.
Question 1. Erythropoeitin (EPO) is a human protein that is produced and secreted by specific cells of the kidney. The EPO gene is located on chromosome #7. Erythropoeitin is a hormone that is produced when the oxygen level in the blood passing through the kidney is low. EPO is secreted into the blood stream and flows past all the cells of your body. The hormone interacts with EPO receptor proteins on the surface of red blood cell precursor cells in the bone marrow and stimulates the activation (transcription and translation) of genes that produce proteins that control the maturation of red blood cells. Increasing the number of red blood cells carrying hemoglobin in the blood increases the ability of the blood to carry oxygen from the lungs to all the cells of your body needing oxygen for aerobic respiration. (from MedicineNet.com)
EPO has become the drug of choice for elite cyclists.
Strenuous events like the Tour de France demand tremendous expenditure
of
energy. Increasing the concentration of red blood cells increases
the ability of the blood to deliver oxygen to the muscles to support
aerobic respiration, which produces ATP to keep the cyclist going
longer
and stronger. Early attempts at "blood doping" were tried by
transfusions of red blood cells from a donor or from the cyclist's own
blood, collected earlier and held for later use. Today blood
doping is most commonly attempted by administering the protein hormone
EPO, produced by
recombinant DNA techniques. EPO stimulates the athlete's bone
marrow to produce more red blood cells. Tests for blood doping
include examination of the blood for abnormal red blood cell content
and urine tests that look for the presence of EPO. Doping tests
during the 2008 Tour de France placed cyclists under suspicion of
using EPO to enhance their performance.
(From The
Guardian, July 12, 2008
Describe and/or diagram the production and secretion of the erythropoetin hormone protein by the cells of the kidney.
Explain the involvement of these components of the cells of the kidney in your description and/or diagram:
Hint: This process is very similar to the production and secretion of milk proteins by human mammary gland cells. See text chapter 3 and lecture outline #6.
Question 2. Draw a diagram of the cell membrane of one of your bone marrow cells (just a small portion of the outer membrane, not the whole cell)
Illustrate and label these cell membrane components:
As part of your drawing, describe how the jobs of the proteins you were asked to include in your membrane drawing are accomplished. Which protein (or proteins) require(s) the chemical bond energy of ATP to do it's/their job(s)?
See textbook chapter 3 on the structure of the Cell Membrane and Signal Transduction (figure 3.8, pg 56), Chapter 4 on passive and active transport (pg 90-94), and chapter 30, Water-Soluble Hormones Trigger Second Messenger Systems (pg 619-620).