Fall 1999 Biology 111 Exam #3 - Bioenergetics

There is no time limit on this test, though I have tried to design one that you should be able to complete within 2.5 hours, except for typing. You are not allowed to use your notes, old tests, or any books, nor are you allowed to discuss the test with anyone until all exams are turned in at 11:30 am on Monday November 22. EXAMS ARE DUE AT CLASS TIME ON MONDAY November 22. You may use a calculator and/or ruler. The answers to the questions must be typed on a separate sheet of paper unless the question specifically says to write the answer in the space provided. If you do not write your answers on the appropriate pages, I may not find them unless you have indicated where the answers are.

Please do not write or type your name on any page other than this cover page. Staple all your pages (INCLUDING THE TEST PAGES) together when finished with the exam.

Name (please print):

Write out the full pledge and sign:

http://www.davidson.edu/student/redbook/honorgeneral.html#honorcode

"On my honor I have neither given nor received unauthorized information regarding this work, I have followed and will continue to observe all regulations regarding it, and I am unaware of any violation of the Honor Code by others."

How long did this exam take you to complete (excluding typing)?

Lab Questions:
6 pts.
1) Interpret these results as completely as you can. The mutagen for this experiment was tobacco extract and the numbers came from this year's results:

Salmonella strain	amount of mutagen (µg/ml)	number of colonies
1535	0	18
1535	15	57
1535	30	115
1535	45	182
1535	60	43
102	0	112
102	15	155
102	30	166
102	45	127
102	60	187

4 pts.
2) What experiment needs to be done next if a substance (for example a new food coloring) is shown to be mutagenic in Salmonella? Explain your answer. You do not have to outline all the steps in this next experiment, just tell me what type of experiment would need to be performed and why.

Lecture Questions:
9 pts.
3) a) In general terms, what happens during the light reaction of photosynthesis? Tell me what is consumed and what is produced.
b) In general terms, what happens during the dark reaction of photosynthesis? Tell me what is consumed and what is produced.

10 pts.
4) a) List the molecules in a leaf can absorb the energy in white light.
b) Describe which wavelengths of light are absorbed by each of your answers in part a.
c) Which of these molecules (from part a) is the last one with the light energy before the energy is sent on to ferredoxin?

6 pts.
5) Explain how oxygen winds up leaving a chloroplast but entering a mitochondrion. In other words, how can the same molecule (O₂) know to leave a chloroplast but enter a mitochondrion?

9 pts.
6) a) In general terms, how is water consumed during photosynthesis?
b) What is produced when water is consumed?
c) Where does each product (answers to part b) go once it is produced?

6 pts.
7) Describe the symbiotic relationship between legumes and Rhizobium. Give one specific example to demonstrate their mutual dependence.

8 pts.
8) a)List the four bioenergetic processes that produce ATP?
b) For each answer in part a), what is the immediate source of energy for this production? Immediate means what is the last source of energy before ATP is created?

12 pts.
9) a) Explain in general terms how carbons cycle through the citric acid cycle.
b) Start with one pyruvate and follow the carbon and all energy. You do not need to name the different sugars but do keep track of the number of carbons.

6 pts.
10) Draw a cartoon of phosphofructoskinase. Make sure you show all the binding sites for substrates and allosteric modulators. You can make the assumption that each of these binding sites is at a different location on the protein. Label each site.

10 pts.
11) What would the symptoms be if a person inherited a mutation in the mitochondrial gene that encodes for one of the ATP synthase subunits?

b) Draw a pedigree of this family. The grandmother has the disease (shaded in symbol) in the P generation, the grand mother produces 1 boy and 1 girl in the F₁ generation, and both of these produced a boy and a girl (total of 2 boys and 2 girls in F₂ generation). Assume that spouses that marry into this family are wild-type.

7 pts.
12) Compare and contrast anaerobic metabolism in your muscles to anaerobic metabolism in yeast used for brewing beer. Describe what is produced in each situation and how much energy is generated in the form of ATP.

7 pts.
13) a) How much ATP does Clostridium tetanii yield from one glucose molecule?
b) What is produced by Clostridium tetanii that is fatal?
c) List two ways this illness can be prevented?