1. Item 1
A. increase the energy of activation for a reaction, thus increasing the reaction rate.
B. decrease the energy of activation for a reaction, thus decreasing the reaction rate.
C. increase ΔG for a reaction, thus increasing the reaction rate.
D. decrease the energy of activation for a reaction, thus increasing the reaction rate.
E. decrease ΔG for a reaction, thus increasing the reaction rate.
1. Item 2
Hemophilia is an X-linked recessive disorder involving blood clotting. If a Mr. Y, who is a hemophiliac, marries Mrs. Z, who is a carrier for hemophilia, and one of their daughters (Miss A, who is not a hemophiliac) marries a normal man (Mr. B), what is the probability that a grandson of Mr. Y and Mrs. Z is a hemophiliac?
A. 25% B. 50% C. 75% D. 100% E. Cannot be determined from the information given
1. Item 3
All of the following could cause increases in resting blood pressure EXCEPT:
A. increased Na+ reabsorption by the kidney.
B. increased heart rate.
C. decreased dehydration.
E. None of the above.
1. Item 4
The functions of the liver include all of the following EXCEPT:
A. formation of blood proteins.
B. regulation of glycogen metabolism.
C. secretion of bile.
D. storage of vitamins.
E. secretion of bicarbonate.
1. Item 5
Osteoblasts, osteoclasts, and osteocytes are the three cell types found in bone tissue. Osteoclasts are activated by:
A. low blood Ca2+ levels and high parathyroid hormone levels.
B. low blood Ca2+ levels and high calcitonin levels.
C. high blood Ca2+ levels and high calcitonin levels.
D. high blood Ca2+ levels and high vitamin D levels.
E. low blood Ca2+ levels and low parathyroid hormone levels.
1. Item 6
Which hormone binds to a receptor on the cell surface?
1. Item 7
Which of the following RNA sequences would be transcribed if the sequence of the DNA coding strand were TATTGCATCAA?
1. Item 8
The pentose phosphate pathway is involved in all of the following EXCEPT:
A. eliminating reactive oxygen species.
B. producing nucleotides.
C. facilitating fatty acid synthesis.
D. forming NADH.
E. generating ribose-5-phosphate.
1. Item 9
When blood pressure is low, the rate of blood filtration drops. The kidney secretes renin to help compensate. The direct effect that renin has in the body is to:
A. generally constrict arterioles to increase peripheral resistance.
B. convert the blood protein angiotensinogen into angiotensin I.
C. convert angiotensin I into angiotensin II, a powerful vasoconstrictor.
D. dilate the renal artery.
E. dilate the glomerular capillaries.
1. Item 10
In designing antibiotics to treat infections caused by facultative anaerobic bacteria in humans, the targets which would be most attractive are inhibitors of bacterial:
A. mRNA splicing.
B. electron transport.
C. poly-A addition for mRNAs.
E. None of the above.
1. Item 11
A double homozygous dominant rabbit with bent ears and big feet is crossed with a double homozygous recessive rabbit with straight ears and small feet. One of the F1s is backcrossed to the double homozygous recessive parent producing an F2 generation with the following ratios of phenotypes: 15 rabbits with bent ears and big feet, 15 rabbits with straight ears and small feet, 5 rabbits with bent ears and small feet, and 5 rabbits with straight ears and big feet. What is the recombination frequency between the gene for ear position and the gene for foot size?
1. Item 12
During muscle contraction, which regions of the sarcomere shorten?
I. A band II. I band III. H band
A. II only
B. I and II only
C. II and III only
D. I and III only
E. I, II, and III
1. Item 13
Which cells in the testes are responsible for secretion of testosterone?
A. Sustentacular (Sertoli) cells
C. Supporting cells
D. Interstitial (Leydig) cells
E. None of the above secrete testosterone.
1. Item 14
What is the primary effect of transposons?
A. Generate mutations and chromosomal rearrangements
B. Facilitate recombination during meiosis
C. Provide protection against integration of lysogenic viruses
D. Increase the affinity of RNA polymerase binding to a promoter
E. Conduct DNA replication proofreading
1. Item 15
The volume of air that remains in the lungs after a complete expiration is called the:
A. residual volume.
B. expiratory reserve volume.
C. functional residual capacity.
D. vital capacity.
E. tidal volume.
1. Item 16
All of the following are methods by which bacteria can achieve genetic diversity EXCEPT:
B. binary fission.
1. Item 17
The dendrites of a single postsynaptic neuron often form synapses with axons of many different presynaptic neurons. The combined input of all the presynaptic neurons ultimately determines whether the postsynaptic neuron will fire an action potential or not. This is known as:
D. temporal summation.
E. spatial summation.
1. Item 18
A hospital has possibly switched the babies of Couples X and Y. Their blood types are as follows:
Couple X: type A and type A Baby 1: type O
Couple Y: type AB and type O Baby 2: type B
Which baby belongs to which couple?
A. Both babies belong to Couple Y.
B. Baby 1 belongs to Couple Y and Baby 2 belongs to Couple X.
C. Baby 1 belongs to Couple X, but Baby 2 could belong to either couple.
D. Baby 1 belongs to Couple X and Baby 2 belongs to Couple Y.
E. Baby 2 belongs to Couple Y, but Baby 1 does not belong to either couple.
1. Item 19
If red blood cells are placed in pure water, which of the following would occur?
A. The cells would swell due to the high osmotic pressure of the water.
B. The cells would shrink due to the high osmotic pressure of the cells.
C. The cells would neither shrink nor swell because red blood cells are isotonic to water.
D. The cells would swell because they are hypotonic to the water.
E. None of the above would occur.
1. Item 20
The net products of glycolysis per glucose molecule are:
A. 4 ATP, 2 NADH, 2 pyruvate
B. 2 ATP, 2 NADH, 2 pyruvate
C. 2 ATP, 4 NADH, 2 lactate
D. 4 ATP, 4 NADH, 4 pyruvate
E. 2 ATP, 2 NADH, 2 lactate
1. Item 21
The hair cells on the basilar membrane represent which of the following receptor types?
1. Item 22
Which of the following cells are produced by the first meiotic division of oogenesis?
B. Primary oocyte and first polar body
C. Secondary oocyte and first polar body
D. Secondary oocyte and second polar body
E. Mature ovum and second polar body
1. Item 23
Potassium moving down its concentration gradient through K+channels in the plasma membrane is an example of:
A. simple diffusion.
B. active transport.
E. facilitated diffusion.
1. Item 24
All of the following can be observed during both meiosis and mitosis EXCEPT:
A. alignment of chromosomes on the metaphase plate.
B. separation of sister chromatids.
C. synapsis of homologous chromosomes.
E. dissolution of the nuclear membrane.
1. Item 25
The opening of which type of ion channel initiates an action potential?
A. Voltage-gated Na+
B. K+ leak
C. Voltage-gated K+
D. Voltage-gated Ca2+
E. Na+/K+ pump
1. Item 26
All of the following are true about Gram– bacteria EXCEPT:
A. they have thin cell walls.
B. they have an inner plasma membrane.
C. they stain a dark purple in Gram stain.
D. they are more resistant to antibiotics than Gram+ bacteria.
E. they have a layer of plasma membrane outside the cell wall.
1. Item 27
When measuring reaction velocity as a function of substrate concentration, a researcher usually keeps the concentration of enzyme at a constant level. What would happen if the enzyme concentration were NOT kept constant?
A. Vmax would remain constant, but V would change.
B. Vmax would remain constant, but Km would change.
C. Vmax would change, but Km would remain constant.
D. both Vmax and Km would change.
E. None of the above would necessarily occur.
1. Item 28
What role does p53, a typical product of a tumor suppressor gene, play in the cell?
A. Signal CD4 T cells to destroy a cell infected with a cancer-causing virus
B. Upregulate transcription of protooncogenes
C. Promote chemotaxis and diapedesis of the cell
D. Trigger apoptosis if abnormal cell growth cannot be halted
E. Stimulate production of additional mitochondria
1. Item 29
Which of the following correctly lists functions of the sympathetic nervous system?
A. Dilate pupils, reduce heart rate, increase blood pressure, inhibit GI tract
B. Increase heart rate, constrict pupils, decrease blood pressure, inhibit GI tract
C. Increase blood pressure, dilate pupils, dilate bronchial tubes, increase heart rate
D. Inhibit GI tract, increase heart rate, constrict bronchial tubes, increase blood pressure
E. Dilate bronchial tubes, stimulate GI tract, increase heart rate, constrict pupils
1. Item 30
All of the following statements about DNA replication are true EXCEPT:
A. it occurs in the 5′ to 3′ direction.
B. both new strands are replicated continuously along the parent strands.
C. prokaryotes use five different DNA polymerases.
D. it requires an RNA primer.
E. it is semiconservative.