Cottonwood, aspen, and willow trees have beige flowers, with no petals, that appear
before the tree’s leaves are out in the spring; and they are dioecious. What does this
indicate about these trees?
A) Their insect pollinators are specialists.
B) Early emerging insects are probably the pollinators.
C) Their pollen is dispersed by wind.
D) The trees are self-pollinating.
The presence of altruistic behavior is most likely due to kin selection, a theory
maintaining that _____.
A) genes enhance survival of copies of themselves by directing organisms to assist
others who share those genes
B) companionship is advantageous to animals because in the future they can help each
other
C) critical thinking abilities are normal traits for animals and they have arisen, like
other traits, through natural selection
D) natural selection has generally favored the evolution of exaggerated aggressive and
submissive behaviors to resolve conflict without grave harm to participants
Scientists have tried raising endangered whooping cranes in captivity by using sandhill
cranes as foster parents. This strategy is no longer used because _____.
A) the fostered whooping cranes’ critical period was variable such that different chicks
imprinted on different “mothers”
B) sandhill crane parents rejected their fostered whooping crane chicks soon after
incubation
C) none of the fostered whooping cranes formed a mating pair-bond with another
whooping crane
D) sandhill crane parents did not properly incubate whooping crane eggs
All types of muscle tissue have _____.
A) striated banding patterns seen under the microscope
B) cells that lengthen when appropriately stimulated
C) a response that can be consciously controlled
D) interactions between actin and myosin
Select the pathway that would lead to the activation of cytotoxic T cells.
A) B cell contact antigen → helper T cell is activated → clonal selection occurs
B) body cell becomes infected with a virus → new viral proteins appear → class I
MHC molecule-antigen complex displayed on cell surface
C) complement is secreted → B cell contacts antigen → helper T cell activated →
cytokines released
D) cytotoxic T cells → class II MHC molecule-antigen complex displayed → cytokines
released → cell lysis
These inside-out membrane vesicles will _____.
A) become acidic inside the vesicles when NADH is added
B) become alkaline inside the vesicles when NADH is added
C) make ATP from ADP and i if transferred to a pH 4 buffered solution after
incubation in a pH 7 buffered solution
D) hydrolyze ATP to pump protons out of the interior of the vesicle to the exterior
A chemical that affects neuronal function but is not stored in presynaptic vesicles is
_____.
A) acetylcholine
B) epinephrine
C) nitric oxide
D) gamma-aminobutyric acid (GABA)
The following questions are based on the accompanying figure.
Which of the following types of signaling is represented in the figure?
A) autocrine
B) paracrine
C) hormonal
D) synaptic
Use the following description to answer the question(s) below.
The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million
years ago and were dominant forms during the Age of the Dinosaurs. Though their
sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition
(they eat pollen) and shelter from the microsporophylls. Upon visiting
megasporophylls, the beetles transfer pollen to the exposed ovules. In cycads, pollen
cones and seed cones are borne on different plants. Cycads synthesize neurotoxins,
especially in the seeds, that are effective against most animals, including humans.
Which feature of cycads makes them similar to many angiosperms?
1. They have exposed ovules.
2. They have flagellated sperm.
3. They are pollinated by animals.
A) 1 only
B) 2 only
C) 3 only
D) 2 and 3
In a typical angiosperm, what is the sequence of structures encountered by the tip of a
growing pollen tube on its way to the egg?
1. micropyle
2. style
3. ovary
4. stigma
A) 4 →? 2 → 3 → 1
B) 4 → 3 → 2 → 1
C) 1 → 3 → 4 → 2
D) 3 → 2 → 4 → 1
Hormone X activates the cAMP second messenger system in its target cells. The
greatest response by a cell would come from _____.
A) applying a molecule of hormone X to the extracellular fluid surrounding the cell
B) injecting a molecule of hormone X into the cytoplasm of the cell
C) applying a molecule of cAMP to the extracellular fluid surrounding the cell
D) injecting a molecule of activated, cAMP-dependent protein kinase into the
cytoplasm of the cell
The chemical reaction illustrated in the accompanying figure _____.
A) is a hydrolysis reaction
B) results in a peptide bond
C) joins two fatty acids together
D) links two polymers to form a monomer
White-crowned sparrows can only learn the “crystallized” song for their species by
_____.
A) listening to adult sparrow songs during a sensitive period as a fledgling, followed by
a practice period until the juvenile matches its melody to its memorized fledgling song
B) listening to the song of its own species during a critical period so that it will imprint
to its own species song and not the songs of other songbird species
C) performing the crystallized song as adults when they become sexually mature, as the
song is programmed into the innate behavior for the species
D) observing and practicing after receiving social confirmation from other adults at a
critical period during their first episode of courtship behavior
Blood is best classified as connective tissue because _____.
A) its cells are separated from each other by an extracellular matrix
B) it contains more than one type of cell
C) its cells can move from place to place
D) it is found within all the organs of the body
Which of the following involves a decrease in entropy?
A) condensation reactions
B) reactions that separate monomers
C) depolymerization reactions
D) hydrolysis reactions
Of the following choices, the epithelium with the shortest diffusion distance is _____.
A) simple squamous epithelium
B) simple columnar epithelium
C) pseudostratified ciliated columnar epithelium
D) stratified squamous epithelium
In the late 1950s, Meselson and Stahl grew bacteria in a medium containing “heavy”
nitrogen (15N) and then transferred them to a medium containing 14N. Which of the
results in the figure above would be expected after one round of DNA replication in the
presence of 14N?
A) A
B) B
C) C
D) D
The best classification system is that which most closely _____.
A) unites organisms that possess similar morphologies
B) conforms to traditional, Linnaean taxonomic practices
C) reflects evolutionary history
D) reflects the basic separation of prokaryotes from eukaryotes
In a cool environment, an ectotherm is more likely to survive an extended period of
food deprivation than would an equally sized endotherm because the ectotherm _____.
A) maintains a higher basal metabolic rate
B) expends more energy per kilogram of body mass than does the endotherm
C) invests little energy in temperature regulation
D) has greater insulation on its body surface
Beetle pollinators of a particular plant are attracted to its flowers’ bright orange color.
The beetles not only pollinate the flowers, but they mate while inside of the flowers. A
mutant version of the plant with red flowers becomes more common with the passage
of time. A particular variant of the beetle prefers the red flowers to the orange flowers.
Over time, these two beetle variants diverge from each other to such an extent that
interbreeding is no longer possible. What kind of speciation has occurred in this
example, and what has driven it?
A) allopatric speciation; ecological isolation
B) sympatric speciation; habitat differentiation
C) allopatric speciation; behavioral isolation
D) sympatric speciation; allopolyploidy
A porcupine eats 3000 J of plant material. Of this, 2100 J is indigestible and is
eliminated as feces, 800 J are used in cellular respiration, and 100 J are used for growth
and reproduction. What is the approximate production efficiency of this animal?
A) 0.03%
B) 3%
C) 10%
D) 33%
Females of many insect species, including honeybee queens, can store gametes shed by
their mating partners in _____.
A) their nests
B) the abdominal tract
C) the uterus
D) the spermatheca
When Cuvier considered the fossils found in the vicinity of Paris, he concluded that the
extinction of species _____.
A) occurs, but that there is no evolution
B) and the evolution of species both occur
C) and the evolution of species do not occur
D) does not occur, but evolution does occur
Use the following figure to answer the questions below.
Referring to the accompanying figure, oxygen would inhibit the CO2 fixation reactions
in _____.
A) cell I only
B) cell II only
C) neither cell I nor cell II
D) both cell I and cell II
The muscles of a recently deceased human can remain in a contracted state, termed
rigor mortis, for several hours, due to the lack of _____.
A) ATP needed to break actin-myosin bonds
B) calcium ions needed to bind to troponin
C) oxygen supplies needed for myoglobin
D) sodium ions needed to fire action potentials
What type of signal is long-lasting and works at night?
A) olfactory
B) visual
C) auditory
D) electrical
Which of the following statements best describes the termination of transcription in
prokaryotes?
A) RNA polymerase transcribes through the polyadenylation signal, causing proteins to
associate with the transcript and cut it free from the polymerase.
B) RNA polymerase transcribes through the terminator sequence, causing the
polymerase to separate from the DNA and release the transcript.
C) Once transcription has initiated, RNA polymerase transcribes until it reaches the end
of the chromosome.
D) RNA polymerase transcribes through a stop codon, causing the polymerase to stop
advancing through the gene and release the mRNA.
The force driving simple diffusion is _____, while the energy source for active transport
is _____.
A) the concentration gradient; ADP
B) the concentration gradient; ATP
C) transmembrane pumps; electron transport
D) phosphorylated protein carriers; ATP
A particular triplet of bases in the template strand of DNA is 5′ AGT 3′. The
corresponding codon for the mRNA transcribed is _____.
A) UCA
B) UGA
C) TCA
D) ACU
If cell X enters meiosis, and nondisjunction of one chromosome occurs in one of its
daughter cells during meiosis II, what will be the result at the completion of meiosis?
A) All the gametes descended from cell X will be diploid.
B) Half of the gametes descended from cell X will be n + 1, and half will be n – 1.
C) 1/4 of the gametes descended from cell X will be n + 1, 1/4 will be n – 1, and 1/2
will be n.
D) Two of the four gametes descended from cell X will be haploid, and two will be
diploid.
Which of the following statements is FALSE regarding the complexity of biological
systems?
A) An understanding of the interactions between different components within a living
system is a key goal of a systems biology approach to understanding biological
complexity.
B) Knowing the function of a component of a living system can provide insight into its
structure and organization.
C) Understanding the chemical structure of DNA reveals how it directs the functioning
of a living cell.
D) An ecosystem displays complex properties not present in the individual communities
within it.
Use the following information to answer the question(s) below.
A plantlike organism on the planet Pandora can have three recessive genetic traits:
bluish leaves, due to an allele (a) of gene A; a feathered stem, due to an allele (b) of
gene B; and hollow roots due to an allele (c) of gene C. The three genes are linked and
recombine as follows:
A geneticist did a testcross with an organism that had been found to be heterozygous for
the three recessive traits and she was able to identify progeny of the following
phenotypic distribution (+ = wild type):
Which of the progeny phenotypes will require recombination between genes A and B?
A) 1, 2, 5, and 6
B) 1, 3, 6, and 7
C) 2, 4, 5, and 8
D) 2, 3, 5, and 7