Recitation 6 : covers lectures Feb. 10 - Feb. 14 and
Sample questions for Exam II
1. Which statement is true
a. under anaerobic condition glycolysis is suppressed
b. under anaerobic conditions no pyruvate is formed in glycolysis
c. under anaerobic conditions pyruvate is reduced rather then oxidized
d. glycolysis requires oxygen e. all statements are incorrect
2. Identify the mismatched pair
a. citric acid cycle -- formation of CO2 b. electron acceptor -- FAD
c. high concentration of protons --- matrix d. citric acid cycle -- matrix
e. cytochrome c -- electron carrier
3. The contribution of the reactions in the citric acid cycle to cellular respiration is
a. the generation of heat energy to increase body temperature
b. to produce all cellular ATP through substrate phosphorylation
c. to oxydize metabolites with the help of oxygen as oxidizing agent
d. none of the above
4. Which of the following is produced during the citric acid cycle ?
a. FADH2 b. Pyruvate c. Reduced electron carriers d. Lactic acid e. Water
5. In presence of a substance which makes the inner mitochondrial membrane permeable to protons
a. The electron transport chain cannot accept any more electrons
b . The citric acid cycle stops c. ATP formation ceases
d. electrons in the electron transport chain cannot be passed from one electron carrier to the next.
6. The statements below describe metabolic processes in the mitochondria that occur during prolonged
absence of oxygen. Which of the statements is correct ?
a. the enzymes of the electron transport chain will not accept electrons from NADH or FADH2
b. The proton gradient across the inner mitochondrial membrane will not be affected
c. the cell will use another source for acetyl CoA ( e.g. from fat degradation)
d. all are incorrect
7. Which of the following statements is true about the mitochondrial electron transport chain ?
a. Complex 1 of the electron transport chain accepts electrons from NAD+
b. the electrons are passed from complex 1 to complex 2
c. while electrons are passed from complex 1 to coenzyme Q, protons are pumped from the matrix into
the cristae
d. the mitochondrial membrane potential drives ATP synthesis
e . all are incorrect
8. The metabolism in brown fat cells causes an increase in body temperature in some mammals by:
a. protons leaking across the cell’s plasma membrane.
b. thermogenin transporting protons across the inner mitochondrial membrane
c. ATP hydrolysis to ADP and P, releasing the energy as heat
d. an increased rate of glycolysis and citric acid cycle.
e. three answers are correct
9. Excited chlorophyll is a better reducing agent than ground-state chlorophyll because
a. excited chlorophyll can release energy by fluorescence.
b. one of the electrons is farther from the atomic nucleus.
c. excited chlorophyll is reduced by NADPH. d. excited chlorophyll can absorbs light better.
10. Calvin Cycle occurs
a. only in conjunction with the light dependent reactions of photosynthesis
b. during in the dark c. during respiration d. two answers are correct
11. Which is not a substrate for ribulose bisphosphocarboxylase (RuBP carboxylase)
a. carbon dioxide b. oxygen c. glyceraldehyde 3-phosphate d. water e. ribulose bisphosphate
12. In C4 plants, the Calvin cycle
a. only occurs when the stomata are closed
b. takes place in the mesophyll and bundle sheets cells cell
c. uses PEP carboxylase instead of RuPB carboxylase because of its greater affinity for CO2
d. all are correct
e. none of the above statements is correct
13 During photosynthesis in C4 plants
a. oxygen is evolved in both mesophyll and bundle sheath cells
b. ATP is formed in the bundle sheet cells mostly via cyclic phosphorylation
c. photorespiration is confined to the mesophyll cells
d. none of the above
14.
a. running the Calvin cycle during the night
b. fixing CO2 into four-carbon compounds in the bundle sheat cells .
c. fixing CO2 into four-carbon compounds in the mesophyll cell during the day
d. using an enzyme that has a higher affinity for CO2 than does RuBP carboxylase
15. Which statement is true. In double stranded DNA
a. purine bases always pair with each other b. any purine base can pair with any pyrimidin base
c. cytosine pairs with thymine via three H-bonds
d. amounts of adenine and guanine are approximately equal e. none of the above
16. Nucleosomes contain
a. histones b. double stranded DNA c. RNA d. two of the above
17 The precursor cells which develop into human sex cells contain:
a. 23 chromosomes b. 46 unattached chromosomes
c. 46 pairs of chromosomes d. 23 attached pairs of chromosomes
18. The arrows indicate the direction in with the new DNA strands are synthesized during replication.
Which diagram is correct ?
19. During the S phase DNA is replicated . If the following segment of a DNA
( 3' ... GCATTATCCG... 5') is replicated, the replicated strand has the following sequence
a 3' ...CGTAATAGGC... 5'
b. 5' ...CGTAATAGGC... 3'
c. 5' ..GCCTATTACG... 3'
d. 3'...GCCTATTACG .. 5'
20. Mitosis followed by cellular division
a. is the mechanism by which human oocytes are formed
b. results in two diploid cells with slightly different DNA
c. produces two haploid cells with identical DNA
d. none of the above
21. Sister chromatids
a. are formed during the S-phase
b. exchange DNA sequences during crossing over
c. have almost identical copies of the chromosomal DNA
d. are the dominant form in which chromosomes exist during the G1 phase
22. Which does occur during the metaphase
a. formation of spindle apparatus b. condensation into chromosomes
c. lining up of chromosomes between the spindle poles d. disappearance of the nuclear envelope
e. the pulling apart of the chromosomes
23 Meiosis produces
a. a daughter cell which is genetically identical to the parent cell
b. a cell with the same number of chromosomes as the parent cell
c. cells with half the number of chromosomes as the parent cells
d. cells with a diploid number of chromosomes
24. Two pairs (each joined by a centromer) of homologous chromosomes
a. can exchange sections of their DNA b. will be separated in anaphase 1
c. consist of a paternal pair and a maternal pair d. all of the above
25. Which statement is not true : cyclin dependent kinases (cdk)
a. need only cyclins for activation
b. cdk/cyclin complex drives the cell through the G2 restriction point
c. initiate phosphorylation of lamin which leads to the disintegration of the nuclear envelope
d. initiate histone phosphorylation, leading to the condensation of DNA fibers into chromosomes
26. Which statement is correct?
a. The p53 tumor suppressor gene codes for a protein that repairs DNA damage
b. Expression of the p53 tumor suppressor gene causes the production of an inhibitor protein that can
deactivate an active cdk/cyclin complex,
c. The p53 tumor suppressor gene codes for a hydrolase that can destroy tumors
d. The p53 tumor suppressor gene codes for a protein that promotes cellular division
27. In Mendel’s experiments, if the allele for tall (T) plants was incompletely dominant over the
allele for short (t) plants, what would be the result of crossing two Tt plants?
a. ¼ would be tall; ½ intermediate height; ¼ short.
b. ½ would be tall; ¼ intermediate height; ¼ short.
c. ¼ would be tall; ¼ intermediate height; ½ short.
d. All the offspring would be tall.
e. All the offspring would be intermediate
28. White eyes is a recessive, sex-linked trait, if a white-eyed female fruit is mated to a red-eyed male,
their offspring should be
a. 50% red-eyed, 50% white-eyed for both sexes. b. all white-eyed for both sexes.
c. all white-eyed males, all red-eyed females. d. all white-eyed females, all red-eyed males.
e. 50% red-eyed males, 50% white-eyed males, all red-eyed females.
29. The parents have the genotypes shown below . Which combination would result in offspring that could have any of the four blood groups
a. AA x
BB b. AB x
AO c. AO x BO
d. OO x AB
30. In a cocker spaniel black coat color (B) is dominant over red (b) and solid color (S) is dominant over spotted (s). If two individuals (both BbSs) are crossed which would be produced.
a. black and spotted b. black and solid c. red an solid
d. red and spotted e. all of the above
31. Which is an example for epistasis
a. the interaction of the alleles for the human blood groups b. incomplete dominance
c. one gene masks the expression of another gene d. non of the above
32. A hemophilic male and a female carrier for the hemophilic trait have a non hemophilic daughter with
Turner syndrome. Non disjunction may have occurred in
a. both parents b. either parent. c. father only d. mother only e. none of the above
33. During meiosis the chromosomes sometimes don’t separate. This is called
a. meiotic failure b. nondisjunction c. gametic infertility d. monosmic zygote
34. Which statement about genetic maps is incorrect?
a. A Gene located near the end of a chromosome is more frequently exchanged during crossing over then
a gene with a locus near the center of the chromosome.
b. Linkage is the tendency of finding two genes on the same chromosome
c. The frequency of breaking a linkage increases if the two genes are located further apart
from each other
d. genetic maps show the position of genes on a chromosome