1.
A (1/2 x 1/2): Assume that genes A and B are not linked. If the probability of allele A in a gamete is 1/2 and the probability of allele B in a gamete is 1/2, then the probability that both A and B are in the same gamete is
a) 1/2 x 1/2
b) 1/2 + 1/2
c) 1/2 / 1/2
d) square root of 1/2
e) | 1/2 - 1/2 |
2.
a (annelida): Closed circulatory system; protostome; many body segments
a) Annelida
b) Mollusca
c) Arthropoda
d) Echinodermata
e) Chordata
3.
a (aorta): The function of which of the following structures is NOT directly related to diffusion or active transport across its membranes?
a) Aorta
b) Small intestine
c) Nephron tubule
d) Capillary
e) Alveolus
4.
a (auxin): Which of the following is primarily responsible for cell elongation, gravitropism, and apical dominance in plants?
a) Auxin
b) Gibberellin
c) Cytokinin
d) Phytochrome
e) Ethylene
5.
a (cambium): Which of the following is an actively dividing tissue in plants?
a) Cambium
b) Xylem
c) Endodermis
d) Phloem
e) Pith
6.
a (cytochrome): A membrane-bound electron carrier found in the electron transport systems of both aerobic respiration and photosynthesis.
a) Cytochrome
b) FADH2
c) NAD+
d) NADP+
e) O2
7.
a (deciduous forest): A prolonged, relatively mild period with ample precipitation alternates with a cold period when plants become dormant.
a) Deciduous forest
b) Tropical rain forest
c) Desert
d) Tundra
e) Taiga
8.
a (decrease in CO2 intake): On a sunny day, the closing of stomata in plant leaves results in
a) a decrease in CO2 intake
b) a shift from C3 photosynthesis to C4 photosynthesis
c) an increase in transpiration
d) an increase in the concentration of CO2 in mesophyll cells
e) an increase in the rate of production of starch
9.
a (DNA ligase): Enzyme used during replication to attach Okazaki fragments to each other
a) DNA ligase
b) DNA polymerase
c) RNA polymerase
d) Restriction enzyme
e) Reverse transcriptase
10.
a (echinoderms): These organisms have radial symmetry and a water vascular system and are generally bottom-dwellers.
a) Echinoderms
b) Annelids
c) Arthropods
d) Cnidarians (coelenterates)
e) Chordates
11.
a (eukaryotic cell): Which of the following is best observed by using a compound light microscope?
a) A eukaryotic cell
b) A virus
c) A DNA sequence
d) The inner structure of a mitochondrion
e) A nuclear pore
12.
a (gastrulation occurs in embryo): Which of the following is correct concerning development of embryos in animals but not in plants?
a) Gastrulation occurs within the embryo.
b) Fertilization produces a diploid embryo.
c) Embryonic cell divisions are mitotic.
d) Fusion of gametes results in a zygote.
e) Cell differentiation occurs.
13.
a (genetic code is degenerate - different DNA sequences can code for same amino acid): Analysis of DNA sequences from two individuals of the same species results in a greater estimate of genetic variability than does analysis of amino acid sequences from the same individuals because
a) different DNA sequences can code for the same amino acid
b) some amino acid variations cannot be detected by protein electrophoresis
c) DNA sequencing is a more reliable technique than protein electrophoresis
d) proteins are more easily damaged than is DNA
e) DNA is more heat-sensitive and therefore varies more
14.
a (glycolysis): Process in which sugar is oxidized to pyruvic acid
a) Glycolysis
b) Krebs cycle (citric acid cycle)
c) Calvin cycle (light-independent reactions of photosynthesis)
d) Light-dependent reactions of photosynthesis
e) Chemiosmosis
15.
a (increases contrast between agar and DNA fragments): A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.
Which of the following is true of the dye used to stain the fragments?
a) It increases the contrast between the agar and the DNA fragments.
b) It must be accounted for when calculating the molecular weight of the fragments.
c) Its charged areas interfere with the migration of the DNA.
d) It is bonded only to the sticky ends of the fragments and can directly determine the sequence of the DNA fragments.
e) It gives a three-dimensional view of the structure of the DNA fragments.
16.
a (microtubule): Membranes are components of all of the following EXCEPT a
a) microtubule
b) nucleus
c) Golgi apparatus
d) mitochondrion
e) lysosome
17.
a (necessary for ATP synthesis by oxidative phosphorylation): Oxygen consumption can be used as a measure of metabolic rate because oxygen is
a) necessary for ATP synthesis by oxidative phosphorylation
b) necessary to replenish glycogen levels
c) necessary for fermentation to take place
d) required by all living organiss
e) required to break down the ethanol that is produced in muscles
18.
A (one dominant, one recessive): Which of the following best describes the parents in a testcross?
a) One individual has the dominant phenotype and the other has the recessive phenotype
b) Both individuals are heterozygous
c) Both individuals have the dominant phenotype
d) Both individuals have the recessive phenotype
e) Both individuals have an unknown phenotype
19.
a (proteins): Synthesized at the ribosome
a) Proteins
b) Carbohydrates
c) Nucleic acids
d) Lipids
e) Steroids
20.
a (reach sexual maturity rapidly): Which of the following best describes opportunistic, or r-strategy, organisms?
a) They reach sexual maturity rapidly.
b) They reach their adult size slowly.
c) They attain a large body size.
d) They live for a long time.
e) The size of their population remains fairly constant.
21.
a (red and blue): In a study of the development of frogs, groups of cells in the germ layers of several embryos in the early gastrula stage were stained with five different dyes that do not harm living tissues. After organogenesis (organ formation), the location of the dyes was noted, as shown in the table below.
Brain - Red
Notochord - Yellow
Liver - Green
Lens of the eye - Blue
Lining of the digestive tract - Purple
Ectoderm would eventually give rise to tissues containing which of the following colors.
a) Red and blue
b) Yellow and purple
c) Green and red
d) Green and yellow
e) Purple and green
22.
a (regulator of gene activity): Gibberellic acid stimulates the cells of germinating grass seeds to produce mRNA molecules that code for hydrolytic enzymes. In this case the role of gibberellic acid can best be described as that of
a) a regulator of gene activity
b) a stimulator of hydrolase secretion
c) a stimulator of DNA replication
d) an allosteric activator of hydrolase
e) an activator of translation
23.
a (retrovirus): Which of the following exists as RNA surrounded by a protein coat?
a) Retrovirus
b) Prion
c) Prokaryote
d) Spirochete
e) Streptococcus
24.
a (shorter cell cycle): Most cells that have become transformed into cancer cells have which of the following characteristics when compared to normal, healthy cells?
a) Shorter cell cycle
b) More carefully regulated rates of cell division
c) Lower rates of mitosis
d) Higher rates of protein translation
e) Identical DNA
25.
a (similar ribosomes and DNA): Which of the following best supports the statement that mitochondria are descendants of endosymbiotic bacteria-like cells?
a) Mitochondria and bacteria possess similar ribosomes and DNA
b) Mitochondria and bacteria possess similar nuclei
c) Glycolysis occurs in both mitochondria and bacteria
d) Both mitochondria and bacteria have microtubules
e) Neither mitochondria nor bacteria possess chloroplasts
26.
a (testis): Secretes steroid hormones that affect secondary sex characteristics
a) Testis
b) Lining of small intestine
c) Anterior pituitary
d) Thyroid
e) Pancreas
27.
a (they influence rate of migration of fragments): A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.
The type and density of the gen are important because
a) they influence the rate of migration of the fragments
b) they may cause some DNA molecules to replicate
c) some DNA nucleotides may be lost due to chemical reactions with the gel
d) some DNA molecules may sink to the bottom and not migrate
e) some DNA molecules may cross-link
28.
a (transcription): Process in which RNA is produced by using a DNA template
a) Transcription
b) Translation
c) Transformation
d) Replication
e) Reverse transcription
29.
a (two genes are far apart on same chromosome): Which of the following is the most likely explanation for a high rate of crossing-over between two genes?
a) The two genes are far apart on the same chromosome.
b) The two genes are both located near the centromere.
c) The two genes are sex-linked.
d) The two genes code for the same protein.
e) The two genes are on different chromosomes.
30.
b (-COOH and -NH2): Which of the following pairs of functional groups characterizes the structure of an amino acid?
a) -NH2 and -COR
b) -COOH and -NH2
c) -COOH and -COR
d) -OH and -NH2
e) -CHO2 - and -NH2
31.
B (1/2): A couple has 5 children, all sons. If the woman gives birth to a sixth child, what is the probability that the sixth child will be a son?
a) 5/6
b) 1/2
c) 1/5
d) 1/6
e) 1/64
32.
b (1/16): Probability that the genotype ccdd will be produced by the parents CcDd x CcDd. Assume that the alleles all assort independently.
a) 0
b) 1/16
c) 1/4
d) 1/2
e) 3/4
33.
b (25%): In sheep, eye color is controlled by a single gene with two alleles. When a homozygous brown-eyed sheep is crossed with a homozygous green-eyed sheep, blue-eyed offspring are produced. If the blue-eyed sheep are mated with each other, what percent of their offspring will most likely have brown eyes.
a) 0%
b) 25%
c) 50%
d) 75%
e) 100%
34.
b (Active transport): Which of the following cellular processes is coupled with the hydrolysis of ATP?
a) Facilitated diffusion
b) Active transport
c) Chemiosmosis
d) Osmosis
e) Na+ influx into a nerve cell
35.
b (actively transported across synaptic cleft): All of the following statements about neurotransmitters are generally true EXCEPT:
a) They may cause depolarization or hyperpolarization of the postsynaptic membrane.
b) They are actively transported across the synaptic cleft.
c) They are released from membrane-bound packets called vesicles.
d) They may be enzymatically degraded at the postsynaptic membrane.
36.
b (aids in seed dispersal): The fruit produced by angiosperms is an evolutionary adaptation that most often
a) nourishes the seeds within the fruit on ripening
b) aids in seed dispersal
c) attracts pollinators
d) inhibits seed germination until favorable environmental conditions occur
e) provides an energy source for the plant egg cell prior to fertilization
37.
b (archaebacteria): Which of the following groups contains prokaryotic organisms capable of surviving the greatest extremes in temperature or salt concentrations?
a) Protista
b) Archaebacteria
c) Plantae
d) Fungi
e) Viruses
38.
b (as bicarbonate ions): Carbon dioxide is transported in human blood primarily in which of the following ways?
a) As oxyhemoglobin
b) As bicarbonate ions
c) Attached to plasma proteins
d) Attached to the amino groups of hemoglobin
e) Attached to the heme groups of hemoglobin
39.
b (baby grasping something): Which of the following behaviors involves the LEAST learning?
a) A lion capturing its prey
b) A newborn human grasping something placed in its hand
c) A mouse finding food in the kitchen of a house
d) A mockingbird singing the song of a different species
e) A chimpanzee finding its way through a forest
40.
b (blood vessels near surface of skin constrict): In mammals, a decrease in body temperature results in which of the following responses?
a) Release of thyroxine decreases the rate of metabolism
b) Blood vessels close to the surface of the skin constrict.
c) Increased secretion of epinephrine restricts the amount of sugar released into the circulatory system.
d) The adrenal glands increase the release of acetylcholine into the circulatory system.
e) Blood vessels in deep muscles constrict so that heat is conserved.
41.
b (carbohydrates): Includes glycogen, chitin, cellulose, and glucose
a) Proteins
b) Carbohydrates
c) Nucleic acids
d) Lipids
e) Steroids
42.
b (chromatids of each chromosome are separated): Which of the following occurs during mitosis but NOT during meiosis I?
a) The chromosomes are pulled to opposite poles of the spindle apparatus
b) The chromatids of each chromosome are separated
c) The nuclear envelope breaks down
d) Both synapsis and crossing-over take place
e) The diploid number of chromosomes is reduced to the haploid number
43.
b (combine with enzymes at active sites to facilitate metabolic reactions): Which of the following statements regarding coenzymes is true?
a) They are essential for metabolic reactions in animals but not in plants.
b) They can facilitate metabolic reactions by combining with enzymes at their active sites.
c) They are minerals that alter the pH of cells and thus increase the probability of chemical reactions.
d) They are synthesized in the rough endoplasmic reticulum of eukaryotic cells.
e) They typically work best at temperatures below 37 degrees Celsius.
44.
b (corpus callosum): A part of the brain used in the transfer of information from one cerebral hemisphere to the other is the
a) medulla oblongata
b) corpus callosum
c) cerebellum
d) hypothalamus
e) pituitary
45.
b (critical period theory): In an experiment on birds learning to sing, young male chicks were exposed only to the songs sung by another species. Later, as they approached maturity, songs of their own species were played for them. When the birds reached maturity, they were able to sing neither the typical song of their species nor the full song of the second species. Which fo the following accounts for this result?
a) Birds innately sing the song typical of their species.
b) Birds pass through a critical period early in life when learning their species-typical song is possible.
c) Birds can learn their typical song if they hear it at any time.
d) Birds must be able to practice their song in order to develop it.
e) Birds are capable of imitating any song that they hear.
46.
b (cytochromes): All of the following are typical components of the plasma membrane of a eukaryotic cell EXCEPT
a) glycoproteins
b) cytochromes
c) cholesterol
d) phospholipids
e) integral proteins
47.
b (decreased respiratory rate): Which of the following physiological effects would likely occur first in a volunteer who was breathing air from which the CO2 was removed?
a) Decreased blood pH
b) Decreased respiratory rate
c) Increased respiratory rate
d) Increased pulse rate
e) Increased blood pressure
48.
b (depend on a concentration gradient): Simple diffusion and facilitated diffusion are related in that both
a) require protein carriers
b) depend on a concentration gradient
c) occur via contractions of cytoskeletal elements attached to membrane proteins
d) are endergonic processes and thus require the hydrolysis of ATP
e) occur in eukaryotic cells but not in prokaryotic cells
49.
b (difference in osmotic potential between the source and the sink): The driving force for the movement of materials in the phloem of plants is
a) gravity
b) a difference in osmotic potential between the source and the sink
c) root pressure
d) transpiration of water through the stomates
e) adhesion of water to vessel elements
50.
b (DNA polymerase): Enzyme used to position nucleotides during DNA replication
a) DNA ligase
b) DNA polymerase
c) RNA polymerase
d) Restriction enzyme
e) Reverse transcriptase
51.
b (earthworm): An animal that has a high surface-area-to-volume ratio of the body, and takes in all the oxygen it needs through its outer epithelium is most likely which of the following?
a) a fish
b) an earthworm
c) a mammal
d) an insect
e) a snake
52.
b (ecosystem): Which of the following levels of organization includes all of the others?
a) Population
b) Ecosystem
c) Community
d) Organism
e) Habitat
53.
b (electron transport chain and chemiosmosis): Which of the following directly produces the most ATP per mole of glucose during aerobic cellular respiration?
a) Glycolysis
b) Electron transport chain and chemiosmosis
c) Substrate-level phosphorylation
d) Kreb's cycle
e) Alcoholic fermentation
54.
b (evaluate which groups are most closely related): A number of different phylogenies (evolutionary trees) have been proposed by scientists. These phylogenies are useful because they can be used to
a) determine when two similar populations of a species evolved into two separate species
b) evaluate which groups of organisms may be most closely related
c) demonstrate that all photosynthetic organisms are members of the Kingdom Plantae
d) demonstrate that natural selection is the prevailing force in evolution
e) demonstrate which taxa (groups of organisms) contain the most highly evolved species
55.
b (FADH2): Coenzyme that transferes electrons from the Krebs cycle to the mitochondrial electron-transport chain at a lower energy level than that of electrons entering at the beginning of the chain
a) Cytochrome
b) FADH2
c) NAD+
d) NADP+
e) O2
56.
b (genetic drift): In a small group of people living in a remote area, there is a high incidence of "blue skin", a condition that results from a variation in the structure of hemoglobin. All of the "blue-skinned" residents can trace their ancestry to one couple, who were among the original settlers of this region. The unusually high frequency of "blue skin" in the area is an example of
a) mutation
b) genetic drift
c) natural selection
d) sexual selection
e) heterozygote advantage
57.
b (glycolysis): Which metabolic process is common to both aerobic cellular respiration and alcoholic fermentation?
a) Krebs cycle
b) Glycolysis
c) Electron transport chain
d) Conversion of pyruvic acid to acetyl CoA
e) Production of a proton gradient
58.
B (Golgi apparatus): Which of the following organelles modifies and packages for secretion the materials produced by the ribosomes?
a) The chloroplast
b) The Golgi apparatus
c) The nucleus
d) The nucleolus
e) The mitochondrion
59.
b (her i allele is recessive to his I(A) allele): A child with blood type A is born to a mother with blood type B. If the father has blood type AB, which of the following statements is correct about the mother?
a) She contributes an I(B) allele, which is recessive to the father's I(A) allele.
b) She contributes an i allele, which is recessive to the father's I(A) allele.
c) She contributes an I(B) allele, which is codominant to the father's I(A) allele.
d) She contributes an i allele, which is codominant to the father's I(B) allele.
e) She is homozygous for the I(B) allele.
60.
b (initial step of CO2 fixation): All of the following are common to C3 and C4 photosynthesis EXCEPT
a) Photolysis
b) Initial step of CO2 fixation
c) Cyclic photophosphorylation
d) Noncyclic photophosphorylation
e) Chemiosmotic phosphorylation
61.
b (krebs cycle): Process in which CO2 is released as a by-product of oxidation-reduction reactions
a) Glycolysis
b) Krebs cycle (citric acid cycle)
c) Calvin cycle (light-independent reactions of photosynthesis)
d) Light-dependent reactions of photosynthesis
e) Chemiosmosis
62.
b (larvae and adults infect different species): Many parasitic flatworms have an intermediate host. This indicates that the
a) flatworms cannot infect humans
b) larval flatworms infect one species, whereas adults infect another species
c) larval flatworms infect only juveniles of a species
d) flatworm adults are microscopic
e) flatworm larvae are parasitic on their parents
63.
b (mitochondrion): The function of which of the following organelles directly requires oxygen?
a) Ribosome
b) Mitochondrion
c) Nucleus
d) Centriole
e) Golgi apparatus
64.
b (multicellular sporophytes): Which of the following characteristics is common to all vascular plants that exhibit an alternation of generations in their life cycle?
a) Large, independent gametophytes
b) Multicellular sporophytes
c) Fertilization in water
d) Diploid spores
e) Seed production
65.
b (pheromones): Which of the following types of chemicals released into the air by female gypsy moths and female silk moths attract males of their respective moth species?
a) Ecdysones
b) Pheromones
c) Auxins
d) Phytotoxins
e) Neurotransmitters
66.
b (pollen tubes deliver sperm to eggs): Flowering plants are capable of fertilization in the absence of water because the
a) processes of pollination and fertilization occur in the soil
b) pollen tubes deliver the sperm to teh eggs
c) eggs develop without sperm by parthenogenesis
d) eggs have a structure that aids in their dispersal by wind
e) sperm contain large amounts of cytoplasm
67.
b (protons down a concentration gradient): During respiration, most ATP is formed as a direct result of the net movement of
a) potassium against a concentration gradient
b) protons down a concentration gradient
c) electrons against a concentration gradient
d) electrons through a channel
e) sodium ions into the cell
68.
b (provides maximum amount of cytoplasm and resources to ovum): Which of the following is true about the production of polar bodies in humans?
a) It increases genetic variability.
b) It provides the maximum amount of cytoplasm and resources to the ovum.
c) It occurs in male and female vertebrates during meiosis I.
d) It is completed prior to fertilization.
e) It results in nondisjunction.
69.
b (small females mate with small males, large females mate with large males): Toads in a particular population vary in size. A scientist observes that in this population, large males mate with females significantly more often than small males do. All the following are plausible hypotheses to explain this observation EXCEPT:
a) Females select large males more often than they select small males as mates.
b) Small females are more likely to mate with small males and large females are more likely to mate with large males.
c) Large males are successful in competing for mates more often than small males are.
d) Large males occupy more breeding territory than small males do.
e) The calls produced by large males are more attractive to females than the calls made by small males.
70.
b (spider & crayfish): In which of the following paris are the organisms most closely related taxonomically?
a) Mushroom . . . oak tree
b) Spider . . . crayfish
c) Bacterium . . . paramecium
d) Sea star (starfish) . . . clam
e) Rosebush . . . diatom
71.
b (synthesize novel DNA molecules): A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained.
The procedures described can be used to do all of the following EXCEPT
a) isolate and purify certain DNA fragments
b) synthesize novel DNA molecules
c) study the activity of restriction enzymes
d) calculate the size of DNA fragments
e) identify the source of DNA material
72.
b (translation): Process in which a protein is assembled at a ribosome
a) Transcription
b) Translation
c) Transformation
d) Replication
e) Reverse transcription
73.
b (transpirational pull): The rate of flow of water through the xylem is regulated by
a) passive transport by the pith
b) the force of transpirational pull
c) the number of companion cells in the phloem
d) active transport by the sieve-tube members
e) active transport by tracheid and vessel cells
74.
b (tropical rain forest): This biome has the greatest diversity of species.
a) Deciduous forest
b) Tropical rain forest
c) Desert
d) Tundra
e) Taiga
75.
b (waste products): Which of the following characterizes glomerular filtrate, the fluid that passes from the blood in the glomerulus into the tubule of the nephron?
a) It is clear in appearance and contains no glucose.
b) It is a concentrated solution of waste products.
c) It is identical to blood plasma.
d) It is blood plasma that lacks most proteins.
e) It is whole blood.
76.
c (1/4): Probability that the genotype TTSs will be produced by the parents TTSs x TtSS. Assume that the alleles all assort independently.
a) 0
b) 1/16
c) 1/4
d) 1/2
e) 3/4
77.
c (activation of all the genes in each cell): In animals, all of the following are associated with embryonic development EXCEPT
a) migration of cells to specific areas
b) formation of germ layers
c) activation of all the genes in each cell
d) inductive tissue interactions
e) cell division at a relatively rapid rate
78.
c (anterior pituitary): Secretes the hormones FSH and LH, which control ovulation
a) Testis
b) Lining of small intestine
c) Anterior pituitary
d) Thyroid
e) Pancreas
79.
c (arthropoda): Coelomate; exoskeleton; jointed appendages
a) Annelida
b) Mollusca
c) Arthropoda
d) Echinodermata
e) Chordata
80.
c (arthropods): These organisms have a chitinous exoskeleton and jointed appendages.
a) Echinoderms
b) Annelids
c) Arthropods
d) Cnidarians (coelenterates)
e) Chordates
81.
c (calvin cycle): Process in which carbon from CO2 is incorporated into organic molecules
a) Glycolysis
b) Krebs cycle (citric acid cycle)
c) Calvin cycle (light-independent reactions of photosynthesis)
d) Light-dependent reactions of photosynthesis
e) Chemiosmosis
82.
c (clone): A large stand of aspen trees may be a group of genetically identical individuals produced by vegetative reproduction. Such a collection of individuals is called a
a) family
b) hybrid
c) clone
d) genus
e) community
83.
c (control movement of materials into vascular cylinder): A major function of the Casparian strip of the endodermal cells of a root is to
a) protect the meristem as the root tip grows through the abrasive soil particles
b) allow for expansion of the vascular cambium as the root grows laterally
c) control the movement of materials into the vascular cylinder of the root
d) initiate lateral root growth
e) serve as a site for the storage of excess sugars in the form of starch
84.
c (Down syndrome): Which of the following can be diagnosed by examining a karyotype of an individual's white blood cells?
a) Sickle cell anemia
b) Alzheimer disease
c) Down syndrome
d) Cystic fibrosis
e) Duchenne muscle dystrophy
85.
c (endoderm only): In a study of the development of frogs, groups of cells in the germ layers of several embryos in the early gastrula stage were stained with five different dyes that do not harm living tissues. After organogenesis (organ formation), the location of the dyes was noted, as shown in the table below.
Brain - Red
Notochord - Yellow
Liver - Green
Lens of the eye - Blue
Lining of the digestive tract - Purple
Tissues stained with the purple dye were probably derived from
a) the ectoderm only
b) the mesoderm only
c) the endoderm only
d) both the ectoderm and the mesoderm
e) both the endoderm and the mesoderm
86.
c (energy can be easily transferred): ATP serves as a common energy source for organisms because
a) it is the smallest energy molecule
b) it stores the least energy of any energy source
c) its energy can be easily transferred to do cellular work
d) it is extremely stable and can be stored in the cell for long periods of time
e) traces of it have been found in fossils of ancient organisms dating back to the beginning of life on Earth
87.
c (falling asleep during bio class): Which of the following is LEAST likely to result in a release of epinephrine (adrenaline) from the adrenal glands?
a) Competing in an athletic event
b) Going out on a first date
c) Falling asleep during a lecture
d) Swimming in a very cold pool
e) Taking a test while unprepared
88.
c (fungi): Which of the following groups is best characterized as being eukaryotic and heterotrophic and having chitinous cell walls?
a) Plantae
b) Animalia
c) Fungi
d) Virus
e) Monera
89.
c (genetically different from parent cell): Which of the following best describes the cells that result from the process of meiosis in mammals?
a) They are diploid.
b) They can be used to repair injuries.
c) They are genetically different from the parent cell.
d) They are genetically identical to all the other cells in the body.
e) They are identical to each other.
90.
c (greater energy supply on lighted side stimulates growth on that side): Which of the following describes the mechanism by which a plant stem grows toward light?
a) The plant seeks light in order to maximize photosynthesis.
b) Nervelike impulses stimulate contractile cells on the lighted side of the stem.
c) Cells on the dark side of the stem elongate more than those on the lighted side.
d) The plant grows into an open area where its leaves will not be shaded by competing plants.
e) The greater energy supply on the lighted side of the stem stimulates metabolism and growth on that side.
91.
c (haploid complement of chromosomes): In most vertebrates, the sperm cell normall contributes which of the following to the new organism?
a) Many mitochondria
b) Significant amounts of RNA
c) A haploid complement of chromosomes
d) Most of the cytoplasm of the zygote
e) Two sex chromosomes
92.
c (hydrogen bonds between oxygen atom of one H2O molecule and hydrogen atom of another H2O molecule): Which of the following is responsible for the cohesive property of water?
a) Hydrogen bonds between the oxygen atoms of two adjacent water molecules
b) Covalent bonds between the hydrogen atoms of two adjacent water molecules
c) Hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule
d) Covalent bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule
e) Hydrogen bonds between water molecules and other types of molecules
93.
C (Its thickness has remained constant over time): All of the following are true about Earth's ozone layer EXCEPT:
a) It shields Earth from most UV radiation.
b) It is composed of O3.
c) Its thickness has remained constant over time.
d) CFC molecules can destroy ozone molecules.
e) It is predicted that a reduction of this layer will result in an increase in human skin cancer.
94.
c (mutations): Which of the following principles is NOT part of Darwin's theory of evolution by natural selection?
a) Evolution is a gradual process that occurs over long periods of time.
b) Variation occurs among individuals in a population.
c) Mutations are the ultimate source of genetic variation.
d) More individuals are born than will survive.
e) Individuals that possess the most favorable variations have the best chance of reproducing.
95.
c (NAD+): An intermediate electron acceptor for oxidations that occur in both glycolysis and in Krebs cycle reactions
a) Cytochrome
b) FADH2
c) NAD+
d) NADP+
e) O2
96.
c (notochord and kidneys develop from endoderm): All of the following correctly describe the fate of the embryonic layers of a vertebrate EXCEPT
a) neural tube and epidermis develop from ectoderm
b) linings of digestive organs and lungs develop from endoderm
c) notochord and kidneys develop from endoderm
d) skeletal muscles and heart develop from mesoderm
e) reproductive organs and blood vessels develop from mesoderm
97.
c (nucleic acids): Used to carry the genetic code
a) Proteins
b) Carbohydrates
c) Nucleic acids
d) Lipids
e) Steroids
98.
c (one embryo, one endosperm): Double fertilization in an ovule of a flowering plant results in which of the following?
a) Two embryos
b) Two seeds in a fruit
c) One embryo and one endosperm
d) Two fruits joined together
e) One endosperm and one cotyledon
99.
c (pancreatic cell producing digestive enzymes): Which of the following cells would most likely have the greatest concentration of densely packed rough endoplasmic reticulum?
a) An amoeba engulfing small ciliates
b) A bioluminescent bacterial cell
c) A pancreatic cell engaged in the production of digestive enzymes
d) A functional phloem cell at maturity
e) An epithelial cell whose DNA is replicating before mitosis
100.
c (pesticides): The LEAST effective means of controlling pest species such as rats or roaches over a long period of time is generally to
a) limit food supplies
b) reduce the number of potential habitats
c) distribute pesticides throughout the habitat
d) introduce predators of the pest
e) introduce a disease which affects only the pest
101.
c (plasma membrane): A prokaryotic cell has which of the following?
a) Centrioles
b) Lysosomes
c) Plasma membrane
d) Mitochondria
e) Endoplasmic reticulum
102.
c (produce large amounts of specific DNA sequences): Which of the following best describes why the polymerase chain reaction is a standard technique used in molecular biology research?
a) It uses inexpensive materials and produces perfect results.
b) It can purify specific sections of a DNA molecule.
c) It can produce large amounts of specific DNA sequences.
d) It can duplicate the entire human genome.
e) It can produce large amounts of mRNA.
103.
c (progesterone): Which of the following hormones is directly responsible for the maintenance of the uterine lining during pregnancy in mammals?
a) Melatonin
b) Oxytocin
c) Progesterone
d) Prolactin
e) FSH (Follicle-stimulating hormone)
104.
c (ribosomes): Prokaryotic and eukaryotic cells generally have which of the following features in common?
a) A membrane-bound nucleus
b) A cell wall made of cellulose
c) Ribosomes
d) Flagella or cilia that contain microtubules
e) Linear chromosomes made of DNA and protein
105.
c (RNA polymerase): Enzyme used in the synthesis of mRNA
a) DNA ligase
b) DNA polymerase
c) RNA polymerase
d) Restriction enzyme
e) Reverse transcriptase
106.
c (specialized for absorbing blue wavelengths of light for photosynthesis): Red algae can grow at greater ocean depths than most other algae can because red algae are
a) specialized for absorbing red wavelengths of light for photosynthesis
b) specialized for absorbing ultraviolet wavelengths of light for photosynthesis
c) specialized for absorbing blue wavelengths of light for photosynthesis
d) unable to use chlorophyll for photosynthesis
e) adapted for chemosynthesis, rather than photosynthesis
107.
c (surface-to-volume ratio increases as diameter decreases): Which of the following is correct concerning a spherical cell?
a) As the diameter decreases, the surface area remains the same.
b) As the diameter decreases, the surface area increases.
c) As the diameter decreases, the surface-to-volume ratio increases.
d) As the diameter increases, the volume decreases.
e) The surface-to-volume ratio is independent of the diameter.
108.
c (transformation): Process in which naked DNA is taken up by a bacterial or yeast cell
a) Transcription
b) Translation
c) Transformation
d) Replication
e) Reverse transcription
109.
c (white blood cells): In humans, the HIV virus primarily attacks which of the following types of cells?
a) Epidermal cells
b) Red blood cells
c) White blood cells
d) Glial cells
e) Neurons
110.
d (1/2): Probability that the genotype Rr will be produced by the parents Rr x rr. Assume that the alleles all assort independently.
a) 0
b) 1/16
c) 1/4
d) 1/2
e) 3/4
111.
d (1/2): Probability that the genotype Aa will be produced by the parents Aa x Aa. Assume that the alleles assort independently.
a) 0
b) 1/16
c) 1/4
d) 1/2
e) 3/4
112.
d (bacteria): Nuclear division in which the chromosome number is reduced from 2n to n is part of the life cycle of all of the following organisms EXCEPT
a) molds
b) ferns
c) insects
d) bacteria
e) protozoans
113.
d (cnidarians): These organisms often have both a polyp form and a medusa form in their life cycle.
a) Echinoderms
b) Annelids
c) Arthropods
d) Cnidarians (coelenterates)
e) Chordates
114.
d (CO2 fixation): Which of the following processes is carried out more efficiently by a C4 plant than by a C3 plant?
a) Light absorption
b) Chemiosmotic coupling
c) Photolysis
d) Fixation of CO2
e) Transport of sugars
115.
d (echinoderm): Internal calcareous skeleton; deuterostome; water-vascular system
a) Annelida
b) Mollusca
c) Arthropoda
d) Echinodermata
e) Chordata
116.
d (either AB or A): A child with blood type A is born to a mother with blood type B. The father must have which of the following blood types?
a) AB only
b) Either AB or B
c) Either AB or O
d) Either AB or A
e) AB or A or O
117.
d (external fertilization): Adaptations that have enabled vertebrates to survive on land include all of the following EXCEPT
a) a water-resistant epidermis
b) development of a bony skeleton
c) development of lungs
d) external fertilization
e) embryos enclosed within membranes
118.
d (feedback inhibition): Certain metabolic pathways are affected by the buildup of a product which interacts with an enzyme catalyzing one of the initial steps of the pathway; this can be an example of
a) transcriptional regulation
b) thermodynamic regulation
c) translational regulation
d) feedback inhibition
e) posttranslational modification
119.
d (fundamental similarity of firefly and tobacco transcription and translation): A tobacco plant can be made to express a gene from fireflies, resulting in the emission of light. Which of the following is the basis for this phenomenon?
a) Chloroplasts can be made to produce light if firefly proteins are injected into plant cells.
b) Fireflies and tobacco plants share a recent common ancestor.
c) Fireflies and tobacco plants are infected by the same kinds of bacteria.
d) Transcription and translation are fundamentally similar in both fireflies and tobacco plants.
e) Most enzymes in fireflies have the same amino acid sequence as the enzymes in tobacco plants.
120.
d (geographic isolation): The different species of finches on the Galapagos islands are believed to have arisen as a result of natural selection acting on populations of finches that had experienced
a) convergent evolution
b) gene flow
c) the bottleneck effect
d) geographic isolation
e) hybrid sterility
121.
d (individual cells become smaller): As the initial cleavage divisions proceed in a frog embryo, which of the following results?
a) The embryo increases in size.
b) The cytoplasmic content of the individual cells increases.
c) The yolk mass increases in size.
d) Individual cells become smaller.
e) Individual cells become haploid.
122.
d (interphase is the longest stage of the cell cycle): A biologist counted 2500 cells from an embryo on a microscope slide and recorded the following data.
Prophase - 125
Metaphase - 50
Anaphase - 50
Telophase - 25
Interphase - 2250
If these cells had been dividing randomly, it could be reasonably concluded that
a) the duration of anaphase is approximately one-half that of telophase
b) prophase is approximately three times as long as telophase
c) metaphase is the shortest state of the cell cycle
d) interphase is the longest stage of the cell cycle
e) the chromosomes can first be seen in prophase
123.
d (intestinal lining produces hormone secretin): Which of the following is the most direct result of the presence of acid chyme in the small intestine?
a) The liver produces insulin.
b) The pancreas produces hydrolytic enzymes.
c) The stomach produces pepsin.
d) The intestinal lining produces the hormone secretin.
e) The gall bladder releases bile.
124.
D (large central vacuole): A student using a light microscope observes a cell and correctly decides that it is a plant cell because
a) ribosomes
b) and endoplasmic reticulum can be seen
c) a cell membrane is present
d) it has a large central vacuole
e) centrioles are present
125.
d (light-dependent reactions of photosynthesis): Process in which O2 is released as a by-product of oxidation-reduction reactions
a) Glycolysis
b) Krebs cycle (citric acid cycle)
c) Calvin cycle (light-independent reactions of photosynthesis)
d) Light-dependent reactions of photosynthesis
e) Chemiosmosis
126.
d (lipids): Used for insulation and buoyancy in marine Arctic animals
a) Proteins
b) Carbohydrates
c) Nucleic acids
d) Lipids
e) Steroids
127.
d (medulla oblongata): The control of breathing is centered in which of the following areas of the brain?
a) Anterior pituitary
b) Corpus callosum
c) Cerebellum
d) Medulla oblongata
e) Cerebrum
128.
d (meiosis I): A spermatocyte produces the following four sperm cells.
[n + 1] [n + 1] [n - 1] [n - 1]
These cells are the result of nondisjunction during which of the following phases?
a) Interphase (G1 or G2)
b) Interphase (S)
c) Mitosis
d) Meiosis I
e) Meiosis II
129.
d (mitochondria and chloroplasts): In a mesophyll cell of a leaf, the synthesis of ATP occurs in which of the following?
I. Ribosomes
II. Mitochondria
III. Chloroplasts
a) I only
b) II only
c) III only
d) II and III only
e) I, II, and III
130.
d (moist membranes): Gas exchange in all living organisms requires
a) Gills
b) Lungs
c) Tracheoles
d) Moist membranes
e) Blood
131.
d (more stomates): All of the following could reduce the yield of photosynthetic products EXCEPT
a) lower concentrations of carbon dioxide in the atmosphere
b) increased photorespiration
c) reduced carbon dioxide concentrations in the air spaces of the leaf
d) increased frequency of stomatal openings
e) fewer Calvin cycle enzymes
132.
d (nitrogen fixation): Which of the following processes is associated with some prokaryotic cells but not with eukaryotic cells?
a) Photosynthesis
b) Aerobic respiration
c) Meiosis
d) Nitrogen fixation
e) Endocytosis
133.
d (number of nucleotides in fragment): A student uses restriction enzymes to cut a DNA molecule into fragments. The digested DNA is loaded into the wells of an agarose gel and the gel is subjected to an electric current. Upon completion of the run, the gel is stained. The rate of migration of the DNA fragments through the agarose gel is determined by the
a) ratio of adenine to cytossine in the fragment
b) presence of hydrogen bonds between base pairs
c) length of time the electrophoresis unit is allowed to operate
d) number of nucleotides in the fragment
e) volume of the starting sample
134.
d (phytochrome): In plants, the initiation of flowering in response to photoperiod is triggered by changes in
a) thylene
b) auxin
c) gibberellic acid
d) phytochrome
e) cytokinin
135.
d (rapid bursts of speciation alternating with long periods of little or no change): Which of the following statements best expresses the concept of punctuated equilibrium?
a) Small variations gradually accumulate in evolving lineages over periods of millions of years.
b) Random mating ensures that the proportions of genotypes in a population remain unchanged from generation to generation.
c) Stability is achieved when selection favors the heterozygote, while both types of homozygotes are at a relative disadvantage.
d) Evolutionary changes consists of rapid bursts of speciation alternating with long periods in which species remain essentially unmodified.
e) Under competition for identical resources, one of the two competing species will be eliminated or excluded.
136.
d (the cell's photoperiod): The rate of division of most vertebrate cells is LEAST likely to be influenced by which of the following?
a) Contact with other cells
b) The availability of nutrients
c) Compounds that inhibit protein synthesis
d) The cell's photoperiod
e) The temperature of the organism
137.
d (thylakoids and a cell wall): A biologist isolates numerous tiny, green-pigmented cells from a sample of lake water. The cells are covered with a mucilaginous sheath. They contain relatively large amounts of chlorophyll a and phycobilin pigments and lack a compact, organized nucleus. Electron microscopy will reveal that these cells also contain which of the following pairs of subcellular structures?
a) Ribosomes and chloroplasts
b) Ribosomes and mitochondria
c) Golgi bodies and a cell wall
d) Thylakoids and a cell wall
e) Chloroplasts and mitochondria
138.
d (thyroid): Releases hormones that increase the rate of cellular respiration throughout the body
a) Testis
b) Lining of small intestine
c) Anterior pituitary
d) Thyroid
e) Pancreas
139.
d (translocation): Which of the following terms refers to both the movement of a ribosome along a piece of mRNA and the movement of a piece of one chromosome to another chromosome?
a) Transduction
b) Transgenesis
c) Transformation
d) Translocation
e) Transplantation
140.
d (true foliage leaves): In the development of a seedling, which of the following will be the last to occur?
a) Initiation of the breakdown of the food reserve
b) Initiation of cell division in the root meristem
c) Emergence of the root
d) Expansion and greening of the first true foliage leaves
e) Imbibition of water by the seed
141.
d (TtYy x TTYy): In peas the trait for tall plants is dominant (T) and the trait for short plants is recessive (t). The trait for yellow seed color is dominant (Y) and the trait for green seed color is recessive (y). A cross between two plants results in 296 tall yellow plants and 104 tall green plants. Which fo the following are most likely to be the genotypes of the parents?
a) TTYY x TTYY
b) TTyy x TTYy
c) TtYy x TtYy
d) TtYy x TTYy
e) TtYY x Ttyy
142.
d (tundra): This biome is dominated by dwarf shrubs, grasses, and sedges that can tolerate long dark winters.
a) Deciduous forest
b) Tropical rain forest
c) Desert
d) Tundra
e) Taiga
143.
d (vascularized tissues for water transport): The fact that tracheophytes can survive on land is due to which of the following?
a) Alternation of generations
b) A dominant gametophyte stage
c) Adaptation to damp habitats
d) Water transport through vascular tissues
e) Mechanisms other than photosynthesis for carbohydrate production
144.
e (0.94): In certain Native American groups, albinism due to a homozygous recessive condition in the biochemical pathway for melanin is sometimes seen. If the frequency of the allele for this condition is 0.06, which of the following is closest to the frequency of the dominant allele in this population? (Assume that the population is in Hardy-Weinberg equilibrium.)
a) 0.04
b) 0.06
c) 0.16
d) 0.36
e) 0.94
145.
e (bilateral symmetry): An animal with anterior, posterior, dorsal, and ventral surfaces on its body must exhibit
a) protostomic development
b) coelomate development
c) segmentation
d) radial symmetry
e) bilateral symmetry
146.
e (both are found in a variety of sizes): Which of the following provides the weakest evidence that mitochondria were once free-living prokaryotes?
a) Mitochondrial ribosomes resemble those of prokaryotes.
b) Mitochondria have DNA that is circular and does not have associated protein.
c) Enzyme pathways on mitochondrial membranes resemble those found on modern prokaryote membranes.
d) Mitochondria reproduce by a process similar to binary fission.
e) Mitochondria and prokaryotes both are found in a variety of sizes.
147.
e (chemiosmosis): Process found in both photosynthesis and cellular respiration
a) Glycolysis
b) Krebs cycle (citric acid cycle)
c) Calvin cycle (light-independent reactions of photosynthesis)
d) Light-dependent reactions of photosynthesis
e) Chemiosmosis
148.
e (chordata): Bilaterally symmetrical; deuterostome; dorsal hollow nerve cord
a) Annelida
b) Mollusca
c) Arthropoda
d) Echinodermata
e) Chordata
149.
e (chordata): Pharyngeal slits; endoskeleton derived from mesoderm; ventral heart
a) Annelida
b) Mollusca
c) Arthropoda
d) Echinodermata
e) Chordata
150.
e (chordates): These organisms have pharyngeal gill slits and a dorsal hollow nerve cord at some time in their development.
a) Echinoderms
b) Annelids
c) Arthropods
d) Cnidarians (coelenterates)
e) Chordates
151.
e (Diatoms): Members of which of the following are the major primary producers in the marine ecosystem?
a) Yeasts
b) Sponges
c) Sporozoans
d) Fishes
e) Diatoms
152.
e (E and F): If organisms A, B, and C belong to the same order but to different families and if organisms D, E, and F belong to the same family but to different genera, which of the following pairs of organisms would be expected to show the greatest degree of structural homology?
a) A and B
b) A and C
c) B and D
d) C and F
e) E and F
153.
e (elongation on the side away from the light source): Plant stems bend toward a light source as a result of increased
a) chlorophyll synthesis on the side of the stem near the light source
b) cell division on the side of the stem near the light source
c) cell division on the side of the stem away from the light source
d) cell elongation on the side of the stem near the light source
e) cell elongation on the side of the stem away from the light source
154.
e (endergonic reaction): A + B + energy ----> AB
Which of the following best characterizes the reaction represented above?
a) Hydrolysis
b) Catabolism
c) Oxidation-reduction
d) Exergonic reaction
e) Endergonic reaction
155.
e (epistasis): Coat color in mice is determined by genes at two loci. When black mice from a particular population mate, they produce offspring in the following ratios: 9 black : 3 brown : 4 white. These results suggest that white coat color is expressed as a result of
a) dominance
b) incomplete dominance
c) codominance
d) a sex-linked trait
e) epistasis
156.
e (ethylene): Fruits often ripen faster when placed in closed paper bags because of the effect of
a) cytokinin
b) abscisic acid
c) CO2
d) gibberellin
e) ethylene
157.
e (glycolysis): Which of the following pathways for the transformation of cellular energy most likely evolved first?
a) Cyclic photophosphorylation
b) Citric acid (Krebs) cycle
c) Calvin cycle
d) C4 photosynthesis
e) Glycolysis
158.
e (heat energy required to establish electron transport chain): Which of the following statements about mitochondrial chemiosmosis is NOT true?
a) A proton gradient is established across the inner membrane of the mitochondrion.
b) The potential energy released from the mitochondrial proton gradient is used to produce ATP.
c) The mitochondrial proton gradient provides energy for muscle contraction.
d) Proteins embedded in the inner mitochondrial membrane play an important role in ATP synthesis.
e) Heat energy is required to establish the electron transport chain.
159.
e (mosses): The gametophyte is the dominant generation in which of the following plants?
a) Dicots
b) Monocots
c) Gymnosperms
d) Ferns
e) Mosses
160.
e (mother carries allele for color blindness): In humans, red-green color blindness is a sex-linked recessive trait. If a man and a woman produce a color-blind son, which of the following MUST be true?
a) The father is color-blind.
b) Both parents carry the allele for color blindness.
c) Neither parent carries the allele for color blindness.
d) The father carries the allele for color blindness.
e) The mother carries the allele for color blindness.
161.
e (movement of H+ into a thylakoid disc during photosynthesis): Which of the following is an example of active transport across a membrane?
a) The movement of water from a nephron into the collecting duct of the kidney
b) The movement of glucose by facilitated diffusion into a liver cell
c) The movement of water from the inside of a cell into a surrounding hypertonic medium
d) The movemtn of Na+ into a neuron as a nerve impulse is generated
e) The movement of H+ into a thylakoid disc during photosynthesis
162.
e (O2-rich atmosphere): All of the following were likely present on the primitive Earth during the evolution of self-replicating molecules EXCEPT
a) amino acids and nucleotides
b) nitrogen
c) simple carbohydrates
d) freestanding liquid water
e) an O2-rich atmosphere
163.
e (O2): The final electron acceptor for cellular respiration
a) Cytochrome
b) FADH2
c) NAD+
d) NADP+
e) O2
164.
e (pancreas): Releases hormones that control blood sugar levels by stimulating glycogen formation or breakdown
a) Testis
b) Lining of small intestine
c) Anterior pituitary
d) Thyroid
e) Pancreas
165.
e (predators often eliminate prey populations): All of the following statements concerning characteristics of predator-prey relationships are correct EXCEPT:
a) A rise in the population of prey is often followed by a rise in the population of predators.
b) A rise in the population of predators is followed by a decrease in the population of prey.
c) Camouflage is an adaptation that protects prey.
d) The production of large numbers of offspring within very short periods of time ensures the survival of some prey populations.
e) The population of predators most often eliminates the population of prey.
166.
E (reproductive isolation): The condition in which there are barriers to successful interbreeding between individuals of different species in the same community is referred to as
a) latent variations
b) sterility
c) structural differences
d) geographic isolation
e) reproductive isolation
167.
e (reverse transcriptase): Enzyme found in retroviruses that produce DNA from an RNA template
a) DNA ligase
b) DNA polymerase
c) RNA polymerase
d) Restriction enzyme
e) Reverse transcriptase
168.
e (reverse transcription): Process that results in the production of cDNA from an RNA molecule
a) Transcription
b) Translation
c) Transformation
d) Replication
e) Reverse transcription
169.
e (roots received moisture, leaves received CO2): A customer observed that a particular potted plant in a restaurant was bigger and greener than other plants in the room. When asked, the owner said that he poured leftover club soda (carbonated water) into that plant's pot every day. Which of the following best explains how the club soda affected that plant's growth?
a) The basic pH of the club soda caused the plant to grow rapidly.
b) The temperature of the club soda promoted faster growth.
c) Oxygen bubbles from the club soda oxygenated the soil.
d) The roots absorbed the CO2 necessary for photosynthesis.
e) The roots received more moisture, and the leaves were exposed to more CO2.
170.
e (taiga): Long, cold, moist winters and short summers are typical of this biome dominated by gymnosperms.
a) Deciduous forest
b) Tropical rain forest
c) Desert
d) Tundra
e) Taiga
171.
E (Trial and error): Which of the following types of behavior describes the way that mice find their way through mazes?
a) Habituation
b) Imprinting
c) Reasoning
d) Instinct
e) Trial and error
