Download BB 350 Practice Exam Name ______ ID #______ Friday, June 27

BB 350 Practice Exam
Name _____________ ID #__________
Friday, June 27, 3174, Noon
General Instructions for Students: This is a 50 minute exam and it is worth 100 points
total.
Read the instructions for each question carefully. If you do not understand the
instructions for a question or what is being asked in a question, raise your hand.
Be careful how you mark your exam. If graders are uncertain about how any
question is answered, it will automatically be marked incorrect. Do not spend too
much time on any one question.
Scores
Section I (12 points)
________________
Section II (36 points) ________________
Section III (52 points) ________________
Total
________________
Important items
A. The logarithm of a number greater than one is a positive number.
B. The logarithm of a number less than one is a negative number
C. For any number X (except X=0), ln (X) = -ln(1/X)
[or log(x) = -log(1/x)]
D. pH = pKa + log {[Salt]/[Acid]}
E. pH = -log[H+] , pOH = -log[OH-], pKa = -Log[Ka], pH + pOH = 14
BB 350 practice exam, Page 1
Section I: The statements in this section can be completed by any of the
lettered responses following it. Each statement may have more than one
answer that is correct, one answer that is correct, or no answers that are correct.
Students should clearly circle only those responses that complete the sentence
to make a correct statement. Points will be awarded for each circled response
that makes a correct statement and for each uncircled response that makes an
incorrect statement. For example, the practice question below has three correct
answers (b,c,d). You would receive eight points if you circled ‘b’,’c’, and ‘d’.
You would receive two points if you circled ‘a’ and ‘b’. You would receive no
points if you circled only ‘a’. If we have uncertainty about whether or not an
answer is marked, it will automatically be counted as a wrongly answered
question. Be clear in your markings.
Practice question #A: Oregon State University
A. is a factory in Portland
B. is located in Corvallis, Oregon
C. has a mascot named Benny Beaver
D. has students from all over the world.
1. With respect to cells and their organelles,
A. eukaryotes have a nucleus
B. bacteria have a nucleus
C. mitochondria have their own DNA
D. there are no single cell eukaryotes
2. With respect to amino acids,
A. all of them have a pI
B. all of them differ in their R groups
C. glycine is the only one lacking an amine group
D. all of them have no charge at pH 7
3. With respect to protein structure
A. the secondary structure refers to how two subunits interact
B. folding is an example of tertiary structure
C. no single subunit proteins have quaternary structure
D. the primary sequence has the least effect on protein structure
Section II: 1. Each sentence below in this section is missing a
word or short phrase to complete it. Fill in the blank as
appropriate to complete the sentence with a correct statement.
Each correctly filled in blank below will be awarded three
points. You MUST be precise in your definitions.
BB 350 practice exam, Page 2
1. What causes peptide bonds to behave like a double bond? ________________
2. The blood pH of your best friend suddenly rises. What happens to the
concentration of oxygen in your best friend’s tissues? ________________
3. Which amino acid is involved in forming the strongest bonds stabilizing
tertiary structure? ________________
4. What is the relationship between the pOH of a solution and the concentration
of protons in it? ________________
5. What type of chromatography relies on a negative charged bead to bind to
positively charged proteins (answer must be specific)? ________________
6. How is the Induced Fit model of catalysis described in one sentence?
________________
7. Define the term ‘substrate’ ________________
8. What type of chromatography uses a separation technique where the largest
molecules move the fastest? ________________
9. What protein is strengthened by vitamin C? ________________
10. Relative to the last question, name an amino acid involved in the process
_______________________
11. What does the term ‘denatured’ mean with respect to protein structure?
________________
BB 350 practice exam, Page 3
12. How much time after exams are returned do students have to get corrections
in? ________________
BB 350 practice exam, Page 4
Section 3 – Problems/Long Answer
1. Fetal hemoglobin differs from adult hemoglobin structurally and in how it binds to
molecules. Describe the structural differences and the different ways it binds molecules
compared to adult hemoglobin (12 points)
2. Name all of the forces described in class that stabilize protein secondary, tertiary, and
quaternary structure. All you need to provide is a list of forces. (12 points)
3. A new amino acid (Ahernium) is discovered that has an R group with two amino
groups and carboxyl group. The pKa values are as follows:
Alpha carboxyl = 2.0
Alpha amino = 8
R-group amino #1 = 11
BB 350 practice exam, Page 5
R-group carboxyl #1 = 3.5
R-group carboxyl #2 = 5.5
Given the information above what would you expect would be the pI of Ahernium? Show
your calculations and your reasoning(12 points)
4. For the following problem, ORGANIZE and LABEL your calculations clearly.
No partial credit will be given without clearly labeled calculations. You do NOT
have to enter the numbers into a calculator. You simply need to show the last step
before punching it in.
1. 800 ml of a 1M buffer (pKa = 5.0) is at its maximum buffering capacity. 0.2 moles of
NaOH is added followed by 0.3 moles of salt.
a. Write an equation for the pH of the resulting solution. (6 points)
b. How much HCl would you have to add to return the solution to its maximum
buffering capacity? (explain your logic – required for credit) (10 points)
BB 350 practice exam, Page 6