In general, a signal transmitted via phosphorylation of a series of proteins _____.
A) results in a conformational change to each protein
B) requires binding of a hormone to an intracellular receptor
C) activates a transcription event
D) generates ATP in the process of signal transduction
Which of the following can be sensed by plants?
I) gravity
II) pathogens
III) wind
IV) light
A) only I and III
B) only I, II, and IV
C) only II, III, and IV
D) I, II, III, and IV
Reactants capable of interacting to form products in a chemical reaction must first
overcome a thermodynamic barrier known as the reaction’s _____.
A) entropy
B) activation energy
C) equilibrium point
D) free-energy content
The phenomenon of fusion is likely to occur when, after a period of geographic
isolation, two populations meet again and _____.
A) an increasing number of infertile hybrids is produced over the course of the next one
hundred generations
B) no reproduction occurs in the hybrid zone
C) an increasing number of viable, fertile hybrids is produced over the course of the
next one hundred generations
D) a decreasing number of viable, fertile hybrids is produced over the course of the next
one hundred generations
In experiments where researchers suspect that a hormone may be responsible for a
certain physiological effect, they may cut the neurons leading to the organ where the
effect being studied occurs. What is the purpose of cutting these neurons?
A) to make sure that the effect is not occurring through actions in the nervous system
B) to make sure that the organ being affected cannot function unless the researchers
stimulate it with an external electrical probe
C) to impair the normal functions of the organ so that the hormonal effect can be more
easily studied
D) to numb the organ so that it can be probed without inducing pain in the lab animal
Three populations of crickets look very similar, but the males have courtship songs that
sound different. What function would this difference in song likely serve if the
populations came in contact?
A) a temporal reproductive isolating mechanism
B) a postzygotic isolating mechanism
C) a behavioral reproductive isolating mechanism
D) a gametic reproductive isolating mechanism
What must be true of any organ described as vestigial?
A) It must be analogous to some feature in an ancestor.
B) It must be homologous to some feature in an ancestor.
C) It must be both homologous and analogous to some feature in an ancestor.
D) It need be neither homologous nor analogous to some feature in an ancestor.
Animals that have external fertilization are most likely to reproduce in which of the
following areas?
A) sand dune
B) polar ice sheet
C) shallow lake
D) tallgrass prairie
Mutant fruit flies that make only one antimicrobial peptide were tested for survival after
infection with Neurospora crassa fungi or with Micrococcus luteus bacteria.
The results shown in the graphs support the hypothesis that _____.
A) adding the defensin gene to such mutants protects them from death by fungal
infection
B) adding the drosomycin gene to such mutants protects them from death by fungal
infection
C) wild-type flies with the full set of genes for antimicrobial peptides are highly
susceptible to these infective agents
D) the presence of any single antimicrobial peptide protects against both infective
agents
Rods exposed to light will _____.
A) depolarize due to the opening of sodium channels
B) hyperpolarize due to the closing of sodium channels
C) depolarize due to the opening of potassium channels
D) hyperpolarize due to the closing of potassium channels
Food web for a particular terrestrial ecosystem
(arrows represent energy flow and letters represent species)
Examine this food web for a particular terrestrial ecosystem. Which species is
autotrophic?
A) A
B) C
C) D
D) E
If a pharmaceutical company wished to design a drug to maintain low blood sugar
levels, one approach might be to design a compound _____.
A) that mimics epinephrine and can bind to the epinephrine receptor
B) that stimulates cAMP production in liver cells
C) to stimulate G protein activity in liver cells
D) that increases phosphodiesterase activity
A cluster of tumor cells that produces and secretes growth factors to induce surrounding
cells to grow and divide is showing which type of cell-to-cell signaling?
A) autocrine
B) paracrine
C) endocrine
D) neuroendocrine
Food web for a particular terrestrial ecosystem
(arrows represent energy flow and letters represent species)
Examine this food web for a particular terrestrial ecosystem. Which species is most
likely a decomposer on this food web?
A) A
B) B
C) C
D) E
In peas, a gene controls flower color such that R = purple and r = white. In an isolated
pea patch, there are 36 purple-flowering plants and 64 white-flowering plants.
Assuming Hardy-Weinberg equilibrium, what is the value of q for this population?
A) 0.36
B) 0.64
C) 0.75
D) 0.80
The steroid hormone that coordinates molting in arthropods is _____.
A) ecdysteroid
B) glucagon
C) thyroxine
D) growth hormone
Some of the largest leaves in the world can be found on plants near the forest floor of
dense tropical rain forests. Which of the following precursors for photosynthesis is most
likely limited in these large leaves?
A) oxygen
B) carbon dioxide
C) glucose
D) light
Ammonia _____.
A) is soluble in water
B) has low toxicity relative to urea
C) is metabolically more expensive to synthesize than urea
D) is the major nitrogenous waste excreted by insects
Based on the data in the figure above, which of the following statements is true?
A) Area 1 could be called a boreal forest/taiga.
B) Area 2 could be called a temperate grassland.
C) Area 1 could be called a tropical wet/rain forest.
D) Area 2 could be tundra.
What does the term insoluble fiber refer to on food packages?
A) cellulose
B) polypeptides
C) starch
D) amylopectin
Fertilization of an egg without activation is most like _____.
A) placing the key in the ignition of a car but not starting the engine
B) resting during halftime of a basketball game
C) preparing a pie from scratch and baking it in the oven
D) walking to the cafeteria and eating lunch
Oxygen has an atomic number of 8 and most commonly, a mass number of 16. Thus,
what is the atomic mass of an oxygen atom?
A) approximately 8 grams
B) approximately 8 daltons
C) approximately 16 grams
D) approximately 16 daltons
Use the following diagram of a hypothetical food web to answer the question(s) below.
The arrows represent the transfer of energy between the various trophic levels.
Which letter represents an organism that could only be a primary consumer?
A) A
B) B
C) C
D) D
Which of the following produces and modifies polysaccharides that will be secreted?
A) lysosome
B) mitochondrion
C) Golgi apparatus
D) peroxisome
For water fleas of the genus Daphnia, switching from a pattern of asexual reproduction
to sexual reproduction coincides with _____.
A) environmental conditions becoming more favorable for offspring
B) greater abundance of food resources for offspring
C) periods of temperature or food stresses on adults
D) exhaustion of an individual’s supply of eggs
A phenotypically normal prospective couple seeks genetic counseling because the man
knows that he has a translocation of a portion of his chromosome 4 that has been
exchanged with a portion of his chromosome 12. Although his translocation is
balanced, he and his wife want to know the probability that his sperm will be abnormal.
What is your prognosis regarding his sperm?
A) 1/4 will carry the two normal chromosomes, 4 and 12, 1/4 will have only the two
translocation chromosomes and no normal chromosomes 4 and 12, and 1/2 will have
both normal and translocated chromosomes.
B) All will carry the same translocation as the father.
C) None will carry the translocation.
D) 1/2 will be normal and the rest will have the father’s translocation.
A mutation that inactivates a regulatory gene of a repressible operon in an E. coli cell
would result in _____.
A) continuous transcription of the structural gene controlled by that regulator
B) complete inhibition of transcription of the structural gene controlled by that
regulator
C) irreversible binding of the repressor to the operator
D) continuous translation of the mRNA because of alteration of its structure
An inhibitory postsynaptic potential (IPSP) occurs in a membrane made more
permeable to _____.
A) potassium ions
B) sodium ions
C) ATP
D) all neurotransmitter molecules
If the sequence of a cDNA has matches with DNA sequences in the genome, then this
genomic DNA is likely to _____.
A) code for a protein
B) code for an rRNA
C) be part of an intron
D) be a regulatory sequence
Which of the following does NOT occur during the Calvin cycle?
A) oxidation of NADPH
B) release of oxygen
C) regeneration of the CO2 acceptor
D) consumption of ATP