Download Final Exam: Multiple Choice Portion Biochem Block Spring 2016

Final Exam: Multiple Choice Portion
Biochem Block
Spring 2016
Name:_________________________________________
Note to students: this is not quite finished yet but I wanted you to have this to work on- I will post a few
more questions later today so please check back...
*** You are allowed to use a calculator for this exam.
***You may use any of the handouts and your main lesson book for this exam. Nothing else. However,
you can email/text/call me if you have any questions. My email is [email protected]; my cell is 310493-0874.
***Before turning in your test, please write your name on the top of every page.
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1. The citric acid cycle takes place in the _____ of mitochondria.
A) matrix
B) cytosol
C) chloroplast
D) inner mitochondrial membrane
E) intermembrane space
2. Phosphodiester bonds make up the connections between ______________________.
A) amino acids in protein
B) amino acids in the á-helix
C) sugars in starch
D) nucleotides in DNA
3. Which noncovalent interaction has the longest range?
A) charge-charge
B) dipole-dipole
C) van der Waals repulsion
D) charge-dipole
E) hydogen bond
4. _______________is a kind of protein 2° structure that can occur in parallel and antiparallel forms.
A) á-helix
B) â-sheet
C) ð-helix
D) B-form
Z-form
5. The melting temperature of DNA ________as the # of GC basepairs increases.
A) increases
B) decreases
C) stays constant
6. The primary uv absorption peak for the nucleic acid bases occurs at ____________________.
A) 410nm
B) 280nm
C) 260 nm
D) none of the above
7. A triple-helical structure is found in the protein_________________________.
A) collagen
B) fibroin
C) hemoglobin
D) amylose
E) glycogen
8. ______is a small, negatively charged, allosteric effector for hemoglobin.
A) H+
B) CO2
C) BPG
D) ATP
E) none of the above
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9. The principal storage polysaccharide in animals is _______________________.
A) á-keratin
B) glycogen
C) amylose
D) glucose
E) cellulose
10. A fatty acid is an example of a(n) ________________molecule.
basic
amphipathic
ampholytic
metastable
highly oxidized
11. (3 pts) If you dissolve 1 mole of hydrochloric acid (a strong acid) in a total volume of 1 L, the
resulting [H+] is:
a) 1 M
b) too high to be measured
c) not able to be calculated
d) fairly small (<< 1 M) because this acid is a weak acid
12. (3 pts) The distance between stacked bases of DNA is:
a) 3 m
b) 3 x 108 m/s
c) 3 D
d) 3 x 10-9 m
e) 3.4 D
f) 34 D
13. (3 pts) Cytochrome c peroxidase has an isoelectric point (pI) of 5.2. A reasonable value for the
charge on this protein at pH 7 is:
A) 0, because the solution is neutral
B) -9
C) +1.8
D) +35
E) none of these charges are possible at the pH given
14. (3 pts) Which of the following is not a feature of the double helix model proposed by Watson and
Crick?
a) a vertical distance of 3.4 D between the base pairs
b) phosphates on the outside, bases on the inside
c) complementary base pairing
d) two strands crossing over each other to form a left-handed helix
e) a rotation of 36o with each basepair
15. A molecule that does not dissolve in water is called _____________________, or “water-fearing”.
A) amphiphobic
B) hydrophilic
C) claustrophobic
D) hydrolytic
E) hydrophobic
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16. Which of the following is not true for water?
A) it has a high surface tension
B) it has a large value of viscosity
C) it has a higher density as a liquid than as a solid
D) it has very strong intermolecular forces
E) it has a high boiling point of 100 oC
F) not applicable; all of these statements are true for water
17. (3 pts) For a favorable reaction, it is always true that:
a) ÄS = -RT ln K
b) ÄH = 0
c) ÄS > 0
d) ÄG < 0
18. (3 pts) The one structural feature not associated with DNA is __________:
a) phosphodiester bonds
b) palindromes
c) á-helix
d) supercoils
e) hairpins
19. (3 pts) Which is true for the molecule shown on the right?
a) it is an alpha helix
b) it is an right-handed helix
c) it is an left-handed helix
d) it could be A-form DNA
20. (3 pts) At pH 9.2, a reasonable guess of the % of acetic acid in the ionized
(negatively charged) form is:
a) 0
b) 10
c) >99
d) 50
e) 8
21. (3 pts) The 2nd law of thermodynamics states that:
a) ÄG0 = -RT ln K
b) ÄU = q-w
c) ÄG = ÄH - TÄS
d) ÄG = ÄG0 + RT ln ([products]/[reactants])
22. (3 pts) Shown at right is a container with different numbers of molecules in
chambers separated by a permeable membrane. Which of the following is true about the
picture?
a) ÄG < 0 for movement of molecules from B to A
b) the entropy will decrease after diffusion of molecules from B to A
c) diffusion from chamber A to B is an exergonic process
d) all of the above statements are true
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23. (3 pts) Oral contraceptives for women resemble which molecule below?
A) ATP
B) pyruvate
C) cholesterol
D) oleate
24. Which statement describes best what happens in glycolysis?
A) fructose is cleaved into two molecules of guanine, absorbing energy
B) glucose is cleaved into two molecules of pyruvate, releasing energy
C) glucose is produced from carbon dioxide
D) electrons flow from NADH to oxygen, producing ATP
25. Which statement describes best what happens in the citric acid cycle?
A) citrate condenses to form a protein
B) glucose is cleaved into two molecules of pyruvate, releasing energy
C) acetyl CoA is oxidized to carbon dioxide, producing the electron-rich compound NADH
D) electrons flow from DNA to protein, creating a fatty acid
26. The breakdown of protein to its amino acids would be a __________ process.
A) catabolic
B) anabolic
C) neither A nor B
27. Mitochondria are responsible for making energy and this happens mainly through:
A) formation of phosphodiester bonds in protein
B) synthesis of cholesterol from acetyl CoA
C) flow of protons from the intermembrane space to the matrix
D) formation of the collagen fiber
28. Peptide sequences are written from
A) N-terminus to C-terminus
B) C-terminus to N-terminus
C) 5' to 3'
D) 3' to 5'
29. The synthesis of a protein from the instructions in the mRNA is called:
A) translation
B) transcription
C) replication
D) prescription
30. Which of the following has quaternary structure?
A) â-sheet
B) myoglobin
C) hemoglobin
D) á-helix
31. Which of the following is (are) true for a peptide bond?
A) it forms a planar unit
B) it is an amide bond
C) it hold sugars together
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