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1
Q

-6- Cortisol is a steroid signaling molecule that communicates its signal by
A. Binding to a membrane receptor protein
B. Binding to an intracellular receptor protein
C. Binding to DNA
D. Binding to mRNA

A

B. Binding to a membrane intracellular receptor protein

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2
Q 
-6- all of the following are second messengers except:
A. cAMP
B. Ca (2+)
C. IP 3
D. FOXP2, a transcription factor
A

D. FOXP2, a transcription factor

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3
Q

-6- gap junction and plasmodesmata allow signaling:
A. By direct contact
B. Across synapsids that span the synaptic cleft between nerve cells
C. Amin nearby cells during early animal development
D. Between different organs of a multicellular organism

A

A. By direct contact

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4
Q

-6- receptor protein activation occurs when:
A. ADP is phosphorylated to ATP
B. ATP is converted to cAMP
C. There is a conformational change in the receptor protein
D. The receptor protein binds to a second messenger

A

C. There is a conformational change in the receptor protein

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5
Q

-6- a consequence of a signaling cascade is that it:
A. Supplies energy to the cell
B. Accelerates mRNA activity
C. Is less susceptible to the impact of mutations
D. Amplifies the signaling response

A

D. Amplifies the signaling response

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6
Q 
-7- if a cell has 46 chromosomes at the beginning of mitosis, then at the separation  phase (anaphase) there would be a total of:
A. 23 chromatids
B. 46 chromosomes
C. 46 chromosomes
D. 92 chromosomes
A

D. 92 chromosomes

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7
Q 
-7- if a cell has 46 chromosomes at the beginning of the first meiotic division, then at the separation phase of the first meiotic division (anaphase I) there would be a total of:
A. 23 chromosomes 
B. 46 chromosomes
C. 46 chromatids
D. 92 chromosomes
A

B. 46 chromosomes

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8
Q

-7- All of the following are true. Except:
A. Spindle fibers are composed largely of micro tubules
B. Centrioles consist of nine triplets of micro tubules arranges in a circle
C. All eukaryotic cells have centrioles
D. All eukaroutic cells have a spindle apparatus

A

C. All eukaryotic cells have centrioles

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9
Q

-6- Insulin is a signaling molecule that
A. is a ligand for a membrane receptor protein
B. Is a ligand for an intracellular receptor protein
C. enters the nucleus and acts as a transcription factor
D. is a second messenger that activates cAMP

A

A. is a ligand for a membrane receptor protein

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10
Q
  1. Cytokinesis begins at
A

Telophase (restoration)

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11
Q
  1. Chromosomes begin migrating to opposite poles during (phase)
A

Anaphase (seperation)

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12
Q
  1. MTOCs migrate to opposite poles during (phase)
A

Prophase (condensation)

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13
Q
  1. Chromosomes replicate during (phase)
A

Interphase (nondividing)

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14
Q 
7. Crossing over occurs during which of the following prophase (condensation) events?
A. prophase of mitosis
B. prophase I of meiosis
C. prophase II of meiosis
D. prophase I and II of meiosis
A

B. the crossed over chromosomes form chiasmata

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15
Q 
7. In typical cell divisions, all of the following contribute to genetic variation EXCEPT:
A. anaphase (seperation) of mitosis
B. anaphase (seperation) of meiosis I
C. fertilization 
D. crossing over
A

A

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16
Q
  1. The two strands of a DNA molecule are connected by
    A. H bonds between the codons and anticodon
    B. H bonds between the bases of one strand and the bases of a second strand
    C. covalent bonds between phosphate groups
    D. covalent bonds between the nitrogen bases
A

B.

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17
Q
  1. All of the following combinations of nucleotides are examples of normal base-pairing EXCEPT:
    A. an adenine DNA nucleotide to a thymin DNA nucleotide
    B. a guanine DNA nucleotide to a cytosine DNA nucleotide
    C. a thyamine RNA nucleotide to an adenine DNA nucleotide
    D. a uracil RNA nucleotide to an adenine DNA nucleotide
A

C

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18
Q
  1. which of the following is true?
    A. Ribosomes contain RNA nucleotides and amino acids
    B. the uracil nucleotide consists of the uracil nitrogen base, a deoxyribose sugar, and a phosphate group
    C. when tRNA attaches to mRNA during translations, cytosine nucleotide base-pair with guanine nucleotides, and adenin nucleotide base-pair with thymine nucleotides.
    D. In eukaryotes, DNA is manufactured in the nucleus and RNA is manufactured in the cytoplasm
A

A

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19
Q 
9. All of the following enzymes are involved in DNA replication EXCEPT:
A. helicase
B. DNA ligase
C. RNA polymerase
D. primase
A

C

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20
Q
  1. ATP, the common energy-carrying molecule, most resembles the
    A. adenine DNA nucleotide
    B. adenine RNA nucleotide
    C. adenine DNA nucleotide with 2 extra phophates
    D. adenine RNA nucleotide with 2 extra phophates
A

D

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21
Q 
9. The end products of translation are 
A. amino acids
B. polypeptides
C. lipids
D. RNA molecules
A

B

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22
Q 
9. which of the following contains a code for a protein?
A. DNA polymerase
B. RNA polymerase
C. rRNA
D. mRNA
A

D

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23
Q
  1. Which of the following changes following the start codon in the mRNA would most likely have the greatest deleterious effect?
    A. a deletion of a single nucleotide
    B. a deletion of a nucleotide triplet
    C. a single nucleotide substitution of the nucleotide occupying the first codon position
    D. a single nucleotide substitution of the nucleotide occupying the third codon position
A

A

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24
Q
  1. The DNA of an elephant and the DNA of a cherry tree will most likely differ in all of the following respects EXCEPT:
    A. the kinds of genes for which the DNA codes
    B. the kinds of nucleotides utilized in forming DNA
    C. the number of DNA nucleotides
    D. the length of DNA molecules
A

B

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25
Q 
9. Protein synthesis consists of all of the following steps EXCEPT:
A. replication
B. transcription
C. translation
D. elongation
A

A

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26
Q 
9. The genetic instructions for forming a polypeptide chain are carried to the ribosome by the
A. tRNA
B. rRNA
C. mRNA
D. DNA
A

C

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27
Q 
9. In bacteria, a small circle of DNA found outside the main chromosome is called a 
A. plasmid
B. cDNA
C. RFLP
D. PCR
A

A

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28
Q
  1. Genetic variation can be introduced into bacteria by all of the following methods EXCEPT:
    A. transfer of DNA between bacteria through pili
    B. DNA amplification
    C. mutation
    D. transformation
A

B

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29
Q 
9. All viruses consist of 
A. DNA and a protein coat
B. RNA and a protein coat
C. a nucleic acid and a protein
D. proteins and polysaccharides
A

C

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30
Q 
9. The mRNA actively being translated in the cytoplasm would have all of the following EXCEPT:
A. a poly-A tail
B. a 5' cap
C. exons
D. introns
A

D

The intervening intron sequences in the mRNA are cleaved from the mRNA by snRNP

31
Q
  1. the lac operon in E. coli is involved in
    A. regulating the expression of a gene
    B. regulating the translation of mRNA
    C. controlling the formation of ribosomes
    D. controlling DNA replication
A

A
operons are DNA segments that include a promoter region, an operator region, and a series of structural genes. Together with a regulatory gene lying outside the operon, the 3 parts of an operon work collectively to control transcription, which results in the regulation of gene expression.

32
Q 
11. which of the following taxa contains organisms that are most distantly related?
A. order
B. class
C. genus
D. family
A

B

Dumb Kings Play Chess On Fine Green Sand

33
Q 
11. prokarotes differ from eukaryotes by all of the following characteristics EXCEPT:
A. kinds of nucleotides in their DNA
B.structure of their flagella
C. structure of their chromosomes
D. methods of cell division
A

A

34
Q 
11. What type of bacteria convert NO2 to NO3?
A. heterotrophic bacteria
B. nitrogen-fixing bacteria
C. nitrifying bacteria
D. purple sulfur bacteria
A

nitrifying bacteria

35
Q 
11. What type of bacteria synthesizes NH3?
A. heterotrophic bacteria
B. nitrogen-fixing bacteria
C. nitrifying bacteria
D. purple sulfur bacteria
A

nitrogen-fixing bacteria

36
Q 
11. What type of photosynthetic bacteria uses H2S as their source of electrons to manufacture organic compounds?
A. heterotrophic bacteria
B. nitrogen-fixing bacteria
C. nitrifying bacteria
D. purple sulfur bacteria
A

purple sulfur bacteria

37
Q 
11. What type of bacteria live in specialized regions of plant roots?
A. heterotrophic bacteria
B. nitrogen-fixing bacteria
C. nitrifying bacteria
D. purple sulfur bacteria
A

Nitrogen-fixing bacteria

38
Q 
11. What type of bacteria live on dead decaying organic matter?
A. heterotrophic bacteria
B. nitrogen-fixing bacteria
C. nitrifying bacteria
D. purple sulfur bacteria
A

Heterotrophic bacteria

39
Q 
11.  All of the following are examples of substances found in bacteria or archaea EXCEPT:
A. peptidoglycans
B. flagellin
C. bacteriorhodopsin
D. chitin
A

D
chitin is found in exoskeleton of arthropods and in the cell walls of fungi.
bacteriorhodopsin is a photosynthetic pigment found in some archaea.

40
Q 
11. All of the following are examples of mutualism EXCEPT:
A. lichens
B. mycorrhizae
C. nitrogen-fixing bacteria in nodules
D. plasmodial slime molds
A

D

A & B are mutualistic relationships between fungi and plants.

41
Q 
13. A nerve impulse is usually transmitted from a motor neuron to a muscle
A. by acetylcholine
B. by an action potential
C. by Ca2+
D. through a reflex arc
A

A: communicates a nerve impulse across the neuromuscular junction

42
Q
  1. What occurs in neurons during the refractory period following an action potential?
    A. Na + moves across the neuron membrane from outside to inside through Na + voltage-gated ion channels
    B. Na + moves across the neuron membrane from inside to outside through Na + voltage-gated ion channels
    C. The Na + voltage-gated ion channels are inactivated and there is no movement of Na+ across the membrane
    D. The outside of the membrane becomes more negative with respect to the inside.
A

C
During the refractory period, the Na+ voltage-gated ion channels are inactivated and unable to respond to a new stimulus. Not until after the resting potential is reestablished do the Na+ channels become responsive to a stimulus once again.

43
Q
  1. If only K+ gates open on the postsynaptic membrane, then:
    A. the postsynaptic membrane releases a neurotransmitter
    B. an excitatory postsynaptic potential (EPSP) is established
    C. the postsynaptic neuron is stimulated
    D. the postsynaptic neuron is inhibited
A

D
If K+ gates are stimulated to open on the postsynaptic membrane, an inhibitory postsynaptic potential (IPSP) is established. This makes the membrane more polarized, and it is more difficult to establish an action potential.

44
Q 
13. which of the following initiates an attack again a specific antigen or pathogen?
A. complement
B. plasma cells
C. interferon
D. macrophages
A

B

Plasma cells are B cells bearing specific antibodies for binding with a specific antigen

45
Q 
13. Which of the following would be activated first in response to a body cell that has been invaded by a virus?
A. cytotoxic T cells 
B. natural killer cells
C. antibodies
D. macrophages
A

A
as part of the cell-mediated immune response, cytotoxic T cells would attack the abnormal body cell first. Once the abnormal cell is lysed, nonspecific attacks by macrophages and other phagocytes would occur.

46
Q 
13. All of the following are involved in the regulation of blood glucose concentration EXCEPT:
A. glucagon
B. insulin
C. the liver
D. HGH
A

D
Human Growth Hormone is secreted by the anterior pituitary. It stimulates bone and cartilage development. Although this stimulation occurs partially as a result of elevating blood glucose, HGH does not actually regulate it.

47
Q
  1. body temperature can be increased by all of the following EXCEPT:
    A. muscle contractions
    B. drinking alcohol, which results in vasodilation
    C. increasing metabolic activity
    D. reducing blood flow to ears
A

B
It is a myth that alcohol warms the body. As a result of vasodilation, blood flow to the extremities is increased. This may make hands an feet feel warmer temporarily, but the total surface area of blood exposed to the surroundings increases, and this results in a loss of heat. As a result, your body temperature, especially of the critical internal organs, will drop.

48
Q
  1. All of the following are examples of countercurrent exchanges EXCEPT:
    A. movement of blood through the fins and tails of marine mammals
    B. the loop of Henle in the nephron
    C. gas exchange in fish gills
    D. gas exchange in human lungs
A

D

49
Q 
13. Most CO2 is transported in the blood
A. as CO2
B. as HCO3-
C. attached to hemoglobin
D. attached to the membrane of erythrocytes
A

B
CO2 enters erythrocytes, where it is convereted to carbonic acid H2CO3 by the enzyme carbonic anhydrase. H2CO3 then dissociates into H+ and HCO3- and diffuses back into the plasma.

50
Q 
13. Gas diffusion in human lungs occurs across membranes of 
A. alveoli
B. bronchi
C. the diaphragm
D. the larynx
A

A

51
Q 
13. Which of the following would normally contain blood with the least amount of oxygen?
A. the left ventricle
B. the left atrium
C. the pulmonary veins
D. the pulmonary arteries
A

D

52
Q 
13. Systolic blood pressure is maintained by the 
A. left atrium
B. right atrium
C. left ventricle
D. right ventricle
A

C

53
Q 
13. In some areas of the human circulatory system, arteries branch into capillaries, merge into veins, then branch into capillaries a second time, before merging again into veins and returning to the hearth. All of the following organs are found in such double capillary bed circuits EXCEPT:
A. the anterior pituitary gland
B. the flomerulus
C. the hypothalamus
D. the lungs
A

D

54
Q 
13. Which of the following is an example of an excretory mechanism?
A. antibodies
B. the digestive tract
C. flame cells
D. neurosecretory cells
A

C

Flame cells function in the excretory system of flatworms.

55
Q
  1. When the filtrate moves through the nephron, solutes
    A. become less concentrated as they move dwon the descending limb of the loop of Henle
    B. become less concentrated as the move up the ascending limb of the loop of Henle
    C. become less concentrated as they move down the collecting duct
    D. are most concentrated when they enter the Bowman’s capsule
A

B

56
Q 
13. Which of the following stimulates the production of more concentrated urine?
A. thyroxin
B. antidiuretic hormone (ADH)
C. insulin
D. glucagon
A

B
ADH is produced by the posterior pituitary, increases the reabsorption of water in the kidneys, making the urine more concentrated

57
Q 
13. In humans, digestion occurs in all of the following locations EXCEPT:
A. the duodenum
B. the mouth
C. the pancreas
D. the small intestine
A

C
Although the pancreas supplies digestive enzymes to the small intenstine (the duodenum), no digestion acually takes place in the pancreas

58
Q 
13. Which of the following is a digestive enzyme found in the stomach?
A. trypsin
B. secretin
C. pepsin
D. bile
A

C
A: digests protein in the small intestine
B: is a hormone (not enzyme) that stimulates he secretion of pancreatic enzymes into the intestine.

59
Q 
13. All of the following are involved in the contraction of muscle cells EXCEPT:
A. actin
B. cAMP
C. myosin
D. tropomyosin
A

B

60
Q
  1. Which of the following is the last step leading up to muscle contraction that occurs just before a myofibril contracts?
    A. Tropomyosin exposes binding sites on actin
    B. ATP binds to myosin
    C. Sarcoplasmic reticulum releases Ca2+
    D. ATP is converted to ADP+Pi
A

A
The order of muscle contraction:
1. ATP binds to myson heads and forms ADP + Pi
2. Action potential travels throughout the T-tubule invaginations, stimulating sarcoplasmic reticulum to release Ca2+.
3. The Ca 2+ causes the tropomyosin to expose the binding sites on the actin. Once this occurs, cross bridges form between myosin and actin, ADP and Pi are released from the myosin heads, and the cross bridges cause the actin to move toward the center of the sarcomere, pulling the Z-lines together and causing the myofibril to shorten.

61
Q 
14. Oogenesis in humans begins
A. during embryonic development
B. at birth
C. at puberty
D. monthly during the menstrual cycle
A

A

But is suspended at prophase I

62
Q 
14. which of the following stimulates ovulation 
A. testosterone
B. progesterone
C. luteinizing hormone (LH)
D. follicle stimulating hormone (FSH)
A

C

63
Q 
14. which of the following promotes the development of the endometrium:
A. testosterone
B. progesterone
C. luteinizing hormone (LH)
D. follicle stimulating hormone (FSH)
A

B

64
Q 
14. follicles in the ovum secret this hormone:
A. testosterone
B. progesterone
C. luteinizing hormone (LH)
D. follicle stimulating hormone (FSH)
A

B

65
Q 
14. WHICH of the following stimulates the testes to produce androgens:
A. testosterone
B. progesterone
C. luteinizing hormone (LH)
D. follicle stimulating hormone (FSH)
A

C

LH stimulates interstitial cells in the testes to produce testosterone and other androgens.

66
Q 
14. The axes of an embryo is influenced by the distribution of:
A. microRNAs
B. the gray crescent
C. GnRH
D. morphgens
A

D
The unequal distribution of morphogens across the embryo generates a morphgen gradient that establishes the anterior/posterior and dorsal/ventral axes of the embryo. The strength of the morphogens in a particular cell signals to the cell where it is relative to the rest of the embryo and stimulates gene expression appropriate to the specific cell.

67
Q 
14. DNA methylation is responsible for 
A. activating trascription factors
B. initiating apoptosis
C. initiating DNA replication
D. inhibiting DNA expression
A

D
Methylation is the process in which methyl groups attach to amino acids in the histone proteins that serve to pack DNA into tight, condensed strands. Methyl groups make it more difficult for the DNA to unwind, thus inhibiting DNA expression.

68
Q
  1. which of the following was most responsible for ending chemical evolution?
    A. natural selection
    B. heterotrophic prokaryotes
    C. photosynthesis
    D. the absence of oxygen in the atmosphere
A

C

69
Q 
10. which of the following generates the formation of adaptations?
A. genetic drift
B. mutations
C. sexual reproduction
D. natural selection
A

D

70
Q 
10. the B blood type allele probably origniated in Asia and subsequently spread to Europe and other regions of the world. This is an example of 
A. natural selection
B. genetic drift
C. gene flow
D. sexual reproduction
A

C

71
Q 
10. the appearance of a new mutation is
A. a random event
B. the result of natural selection
C. the result of sexual reproduction
D. usually a beneficial event
A

A

72
Q
  1. which of the following is an example of sexual selection?
    A. dark-colored peppered moths in London at the beginning of the Industrial Revolution
    B. the mane of a lion
    C. insecticide resistance in insects
    D. Darwin’s finches in the Galapagos Islands
A

B

73
Q
  1. after test-cross experiments, it was determined that the frequencies of homozygous dominant, heterozygous and homozyfous recessive individuals for a particular trait were 32%, 64%, and 4%, respectively. The dominant and recessive allele frequencies are
    A 0.2 and 0.8, respectively
    B. 0.32 and 0.68, respectively
    C. 0.36 and 0.64, respectively
    D. cannot be determined because the population is not in a Hardy-Weinberg equilibrium
A

D

Biology-Cell and Molecular Biology (2 decks)

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