The pancreas is involved in the digestion of _____.
I) protein
II) fat
III) nucleic acids
IV) carbohydrates
A) I and III
B) I, II, and IV
C) II, III, and IV
D) I, II, III, and IV
Which of the functional groups below acts most like an acid in water?
A) amino
B) carbonyl
C) carboxyl
D) hydroxyl
Which of the following is a feature of the tube-within-a-tube body plan in most animal
phyla?
A) The outer tube consists of a hard exoskeleton.
B) The outer tube consists of digestive organs.
C) The mouth and anus form the ends of the inner tube.
D) The two “tubes” are separated by tissue that comes from embryonic endoderm.
The contraction of skeletal muscles is based on _____.
A) myosin filaments coiling up to become shorter
B) actin and myosin filaments both coiling up to become shorter
C) actin cross-bridges binding to myosin and transitioning from a high-energy to a
low-energy state
D) myosin cross-bridges binding to actin and transitioning from a high-energy to a
low-energy state
Which of the following statements is true of the pine life cycle?
A) The pine tree is a gametophyte.
B) Male and female gametophytes are in close proximity during gamete synthesis.
C) Conifer pollen grains contain male gametophytes.
D) Double fertilization is a relatively common phenomenon.
Nitrogen fixation is a process that_____.
A) recycles nitrogen compounds from dead and decaying materials
B) converts ammonia to ammonium
C) releases nitrate from the rock substrate
D) converts nitrogen gas into ammonia
Active transport of amino acids in plants at the cellular level requires _____.
A) NADP and channel proteins
B) xylem membranes and channel proteins
C) sodium/potassium pumps and xylem membranes
D) ATP, transport proteins, and a proton gradient
Human immunodeficiency virus (HIV) infects cells that have both CD4 and CCR5 cell
surface molecules. The viral nucleic acid molecules are enclosed in a protein capsid,
and the protein capsid is itself contained inside an envelope consisting of a lipid bilayer
membrane and viral glycoproteins. One hypothesis for viral entry into cells is that
binding of HIV membrane glycoproteins to CD4 and CCR5 initiates fusion of the HIV
membrane with the plasma membrane, releasing the viral capsid into the cytoplasm. An
alternative hypothesis is that HIV gains entry into the cell via receptor-mediated
endocytosis, and membrane fusion occurs in the endocytotic vesicle. To test these
alternative hypotheses for HIV entry, researchers labeled the lipids on the HIV
membrane with a red fluorescent dye.
What would be observed by live-cell fluorescence microscopy immediately after HIV
entry if HIV is endocytosed first, and then later fuses with the endocytotic vesicle
membrane?
A) A spot of red fluorescence will be visible on the infected cell’s plasma membrane,
marking the site of membrane fusion and HIV entry.
B) The red fluorescent dye-labeled lipids will appear in the infected cell’s interior.
C) A spot of red fluorescence will diffuse in the infected cell’s cytoplasm.
D) A spot of red fluorescence will remain outside the cell after delivering the viral
capsid.
An example of a properly functioning homeostatic control system is seen when _____.
A) the core body temperature of a runner rises gradually from 37C to 45C
B) the kidneys excrete salt into the urine when dietary salt levels rise
C) a blood cell shrinks when placed in a solution of salt and water
D) the blood pressure increases in response to an increase in blood volume
Protein kinase is an enzyme that _____.
A) functions as a second messenger molecule
B) serves as a receptor for various signal molecules
C) activates or inactivates other proteins by adding a phosphate group to them
D) produces second messenger molecules
The human X and Y chromosomes _____.
A) are both present in every somatic cell of males and females
B) are the same size and have the same number of genes
C) include genes that determine an individual’s sex
D) are called autosomes
Which of these are NOT embedded in the hydrophobic portion of the lipid bilayer at
all?
A) transmembrane proteins
B) integral proteins
C) peripheral proteins
D) All of these are embedded in the hydrophobic portion of the lipid bilayer.
According to the biological species concept, for speciation to occur, _____.
A) the number of chromosomes in the gene pool must change
B) changes to centromere location or chromosome size must occur within the gene pool
C) large numbers of genes that affect numerous phenotypic traits must change
D) at least one gene, affecting at least one phenotypic trait, must change
The symbols +, -, and o are to be used to show the results of interactions between
individuals and groups of individuals in the examples that follow. The symbol + denotes
a positive interaction, – denotes a negative interaction, and o denotes where individuals
are not affected by interacting. The first symbol refers to the first organism mentioned.
What interactions exist between a tick on a dog and the dog?
A) +/o
B) +/-
C) o/o
D) -/-
A newspaper ad for a local toy store indicates that an inexpensive toy microscope
available for a small child is able to magnify specimens nearly as much as the more
costly microscope available in your college lab. What is the primary reason for the price
difference?
A) The toy microscope does not have the same fine control for focus of the specimen.
B) The toy microscope magnifies a good deal, but has low resolution and therefore poor
quality images.
C) The college microscope produces greater contrast in the specimens.
D) The toy microscope usually uses a different wavelength of light source.
A compound contains hydroxyl groups as its predominant functional group. Therefore,
this compound _____.
A) lacks an asymmetric carbon and is probably a fat or lipid
B) should dissolve in water
C) should dissolve in a nonpolar solvent
D) will not form hydrogen bonds with water
Agricultural lands frequently require nutrient augmentation because _____.
A) nitrogen-fixing bacteria are not as plentiful in agricultural soils because of the use of
pesticides
B) the nutrients that become the biomass of plants are not cycled back to the soil on
lands where they are harvested
C) land that is available for agriculture tends to be nutrient-poor
D) cultivation of agricultural land inhibits the decomposition of organic matter
The advantage of light microscopy over electron microscopy is that _____.
A) light microscopy provides for higher magnification than electron microscopy
B) light microscopy provides for higher resolving power than electron microscopy
C) light microscopy allows one to view dynamic processes in living cells
D) light microscopy provides higher contrast than electron microscopy
A large proportion of archaeans are extremophiles, so called because they inhabit
extreme environments with high acidity, salinity, and/or temperature. Such
environments are thought to have been much more common on the primitive Earth.
Thus, modern extremophiles survive only in places that their ancestors became adapted
to long ago. Which of the following is, consequently, a valid statement about modern
extremophiles, assuming that their habitats have remained relatively unchanged?
A) Among themselves, they should share relatively few ancestral traits, especially those
that enabled ancestral forms to adapt to extreme conditions.
B) On a phylogenetic tree whose branch lengths are proportional to the amount of
genetic change, the branches of the extremophiles should be shorter than the
non-extremophilic archaeans.
C) They should contain genes that originated in eukaryotes that are the hosts for
numerous species of bacteria.
D) They should currently be undergoing a high level of horizontal gene transfer with
non-extremophilic archaeans.
You have just sequenced a new protein found in mice and observe that sulfur-containing
cysteine residues occur at regular intervals. What is the significance of this finding?
A) Cysteine residues are required for the formation of α-helices and β-pleated sheets.
B) It will be important to include cysteine in the diet of the mice.
C) Cysteine residues are involved in disulfide bridges that help form tertiary structure.
D) Cysteine causes bends, or angles, to occur in the tertiary structure of proteins.
The Dunkers are a religious group that moved from Germany to Pennsylvania in the
mid-1700s. They do not marry with members outside their own immediate community.
Today, the Dunkers are genetically unique and differ in gene frequencies, at many loci,
from all other populations including those in their original homeland. Which of the
following likely explains the genetic uniqueness of this population?
A) population bottleneck and Hardy-Weinberg equilibrium
B) heterozygote advantage and stabilizing selection
C) mutation and natural selection
D) founder effect and genetic drift
The experimental approach taken in current biological investigations presumes that
_____.
A) simple organic compounds can be synthesized in the laboratory from inorganic
precursors, but complex organic compounds like carbohydrates and proteins can be
synthesized only by living organisms
B) a life force ultimately controls the activities of living organisms and this life force
cannot be studied by physical or chemical methods
C) living organisms are composed of the same elements present in nonliving things,
plus a few special trace elements found only in living organisms or their products
D) living organisms can be understood in terms of the same physical and chemical laws
that can be used to explain all natural phenomena
Refer to the figure above. What bases will be added to the primer as DNA replication
proceeds? The bases should appear in the new strand in the order that they will be
added starting at the end of the primer.
A) C, A, G, C, A, G, A
B) T, C, T, G, C, T, G
C) A, G, A, C, G, A, C
D) G, T, C, G, T, C, T
All protists are _____.
A) unicellular
B) eukaryotic
C) symbionts
D) mixotrophic
The eight climographs below show yearly temperature (line graph and left vertical axis)
and precipitation (bar graph and right vertical axis) averages for each month for some
locations on Earth.
Which climograph shows the climate for location 3?
A) B
B) C
C) D
D) E
Gene S controls the sharpness of spines in a type of cactus. Cactuses with the dominant
allele, S, have sharp spines, whereas homozygous recessive ss cactuses have dull
spines. At the same time, a second gene, N, determines whether or not cactuses have
spines. Homozygous recessive nn cactuses have no spines at all. A cross between a
true-breeding sharp-spined cactus and a spineless cactus would produce_____.
A) all sharp-spined progeny
B) 50% sharp-spined, 50% dull-spined progeny
C) 25% sharp-spined, 50% dull-spined, 25% spineless progeny
D) It is impossible to determine the phenotypes of the progeny.
Darwin’s finches, collected from the Galpagos Islands, illustrate which of the
following?
A) mutation frequency
B) ancestors from different regions
C) adaptive radiation
D) vestigial anatomical structures
E) the accuracy of the fossil record
Feeding behavior with a high energy intake-to-expenditure ratio is called _____.
A) autotrophy
B) heterotrophy
C) search scavenging
D) optimal foraging
The following figure depicts the outline of a large fairy ring that has appeared overnight
in an open meadow, as viewed from above. The fairy ring represents the furthest
advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the
soil surface.
At which location should one find the lowest concentration of fungal enzymes,
assuming that the enzymes do not diffuse far from their source, and that no other fungi
are present in this habitat?
A) A
B) B
C) C
D) D
The figure below depicts changes to the amount of DNA present in a recipient cell that
is engaged in conjugation with an Hfr cell. Hfr cell DNA begins entering the recipient
cell at Time A. Assume that reciprocal crossing over occurs (in other words, a fragment
of the recipient’s chromosome is exchanged for a homologous fragment from the Hfr
cell’s DNA).
What is occurring at Time C that is decreasing the DNA content?
A) crossing over
B) cytokinesis
C) degradation of DNA that was not retained in the recipient’s chromosome
D) reversal of the direction of conjugation
In eukaryotes, general transcription factors _____
A) bind to other proteins or to the TATA box
B) inhibit RNA polymerase binding to the promoter and begin transcribing
C) usually lead to a high level of transcription even without additional specific
transcription factors
D) bind to sequences just after the start site of transcription
If recombination frequency is equal to distance in map units, what is the approximate
distance between genes A and B?
A) 3 map units
B) 6 map units
C) 15 map units
D) 30 map units
Which functional group(s) shown above is (are) present in all amino acids?
A) A and B
B) B and D
C) C only
D) B and C
Will treating a viral infection with antibiotics affect the course of the infection?
A) No; antibiotics work by inhibiting enzymes specific to bacteria. Antibiotics have no
effect on eukaryotic or virally encoded enzymes.
B) No; antibiotics do not kill viruses because viruses do not have DNA or RNA.
C) Yes; antibiotics activate the immune system, and this decreases the severity of the
infection.
D) Yes; antibiotics can prevent viral entry into the cell by binding to host-receptor
proteins.
Two competing hypotheses to account for the increase in the number of Hox genes from
the last common ancestor of bilaterians to the last common ancestor of insects and
vertebrates are: (1) a single duplication of the entire four-gene cluster, followed by the
loss of one gene, and (2) three independent duplications of individual Hox genes. To
prefer the first hypothesis on the basis of parsimony requires the assumption that _____.
A) the duplication of a cluster of four Hox genes is equally likely as the duplication of a
single Hox gene
B) there is an actual process by which individual genes can be duplicated
C) genes can exist is spatial groupings called clusters
D) clusters of genes can undergo disruption, with individual genes moving to different
chromosomes during evolution