Fossils of Thrinaxodon, a species that lived during the Triassic period, have been found
in both South Africa and Antarctica. Thrinaxodon had a reptile-like skeleton and laid
eggs, but small depressions on the front of its skull suggest it had whiskers and,
therefore, fur. Thrinaxodon may have been warm-blooded. The fossils of Thrinaxodon
are consistent with the hypothesis that _____.
A) fossils found in a given area look like the modern species in that same area
B) the environment where it lived was very warm
C) mammals evolved from a reptilian ancestor
D) Antarctica and South Africa separated after Thrinaxodon went extinct
CD4 and CD8 are _____.
A) proteins secreted by antigen-presenting cells
B) receptors present on the surface of natural killer cells
C) molecules present on the surface of T cells where they interact with major
histocompatability (MHC) molecules
D) molecules on the surface of antigen-presenting cells where they enhance B cell
activity
Which of the following is the correctorder of floral organs from the outside to the inside
of a complete flower?
A) petals → sepals → stamens → carpels
B) sepals → stamens → petals → carpels
C) spores → gametes → zygote → embryo
D) sepals → petals → stamens → carpels
Phloem transport is described as being from source to sink. Which of the following
would most accurately complete this statement about phloem transport as applied to
most plants in the late spring?
Phloem transports ________ from the ________ source to the ________ sink.
A) amino acids; root; mycorrhizae
B) sugars; leaf; apical meristem
C) proteins; root; leaf
D) sugars; woody stem; root
A gelatinous seaweed that grows in shallow, cold water and undergoes heteromorphic
alternation of generations is most probably what type of alga?
A) red
B) green
C) brown
D) yellow
During a one-year study, researchers found no difference in treehopper populations in
any of their control and experimental groups. What could they measure during the
second year to gain information about why this might have occurred?
A) Measure the number of ant females.
B) Measure the relative sizes of the treehoppers.
C) Measure the relative abundance of jumping spiders.
D) Measure the relative sizes of different ant species.
You discover a new species of bacteria that grows in aquatic environments with high
salt levels. While studying these bacteria, you note that their internal environment is
similar to the salt concentrations in their surroundings. You also discover that the
internal salt concentrations of the bacteria change as the salt concentration in their
environment changes. The new species can tolerate small changes in this way, but dies
from large changes because it has no mechanism for altering its own internal salt levels.
What type of homeostatic mechanism is this species using to regulate its internal salt
levels?
A) conformation
B) regulation
C) integration
D) assimilation
A ball-and-socket joint connects _____.
A) the radius to the ulna
B) the radius to the humerus
C) the ulna to the humerus
D) the humerus to the scapula
Use the following figure to answer the questions below.
The citric acid cycle.
If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and
citric acid in the citric acid cycle shown in the accompanying figure?
A) Oxaloacetate will decrease and citric acid will accumulate.
B) Oxaloacetate will accumulate and citric acid will decrease.
C) Both oxaloacetate and citric acid will decrease.
D) Both oxaloacetate and citric acid will accumulate.
If an amphibian zygote is manipulated so that the first cleavage plane fails to divide the
gray crescent, then _____.
A) the daughter cell with the entire gray crescent will die
B) both daughter cells will develop normally, because amphibians are totipotent at this
stage
C) only the daughter cell with the gray crescent will develop normally
D) both daughter cells will develop abnormally
The oceans affect the biosphere by _____.
I) producing a substantial amount of the biosphere’s oxygen
II) adding carbon dioxide to the atmosphere
III) being the source of most of Earth’s rainfall
IV) regulating the pH of freshwater biomes and terrestrial groundwater
A) only I and III
B) only II and IV
C) only I, II, and IV
D) only I, II, and III
Substrate-level phosphorylation accounts for approximately what percentage of the ATP
formed by the reactions of glycolysis?
A) 0%
B) 2%
C) 38%
D) 100%
When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction
reaction, the molecule becomes _____.
A) hydrolyzed
B) oxidized
C) reduced
D) an oxidizing agent
Once a cell completes mitosis, molecular division triggers must be turned off. What
happens to MPF during mitosis?
A) It is completely degraded.
B) It is exported from the cell.
C) The cyclin component of MPF is degraded.
D) The Cdk component of MPF is degraded and exported from the cell.
The generative cell of male angiosperm gametophytes is haploid. This cell divides to
produce two haploid sperm cells. What type of cell division does the generative cell
undergo to produce these sperm cells?
A) mitosis
B) meiosis
C) mitosis without subsequent cytokinesis
D) meiosis without subsequent cytokinesis
Generally speaking, deserts are located in places where air masses are usually _____.
A) tropical
B) humid
C) rising
D) descending
During aerobic respiration, which of the following directly donates electrons to the
electron transport chain at the lowest energy level?
A) NADH
B) ATP
C) ADP + i
D) FADH2
The common edible frog of Europe is a hybrid between two species, Rana lessonae and
Rana ridibunda. The hybrids were first described in 1758 and have a wide distribution,
from France across central Europe to Russia. Both male and female hybrids exist, but
when they mate among themselves, they are rarely successful in producing offspring.
What can you infer from this information?
A) Postzygotic isolation exists between the two frog species.
B) Prezygotic isolation exists between the two frog species.
C) These two species are likely in the process of fusing back into one species.
D) The hybrids form a separate species under the biological species concept.
What is the name of the functional group shown in the figure below?
A) carbonyl
B) ketone
C) aldehyde
D) carboxyl
For a neuron with an initial membrane potential at -70 mV, an increase in the movement
of potassium ions out of that neuron’s cytoplasm would result in the _____.
A) depolarization of the neuron
B) hyperpolarization of the neuron
C) replacement of potassium ions with sodium ions
D) replacement of potassium ions with calcium ions
Analysis of a blood sample from a fasting individual who had not eaten for twenty-four
hours would be expected to reveal high levels of _____.
A) insulin
B) glucagon
C) gastrin
D) glucose
Refer to the following figure to answer the questions below.
How many neutrons are present in the nucleus of a phosphorus-32 (32P) atom (see the
figure above)?
A) 15
B) 16
C) 17
D) 32
What is the hydrogen ion (H+) concentration of a solution of pH 8?
A) 8 M
B) 8 x 10-6M
C) 10-8M
D) 10-6M
If isolated plant cells with a water potential averaging -0.5 MPa are placed into a
solution with a water potential of -0.3 MPa, which of the following would be the most
likely outcome?
A) The pressure potential of the cells would increase.
B) Water would move out of the cells.
C) The cell walls would rupture, killing the cells.
D) Solutes would move out of the cells.
A population of viruses with similar characteristics is called a _____.
A) strain
B) species
C) type
D) genome
Some molecular data place the giant panda in the bear family (Ursidae) but place the
lesser panda in the raccoon family (Procyonidae). If the molecular data best reflect the
evolutionary history of these two groups, then the morphological similarities of these
two species is most likely due to _____.
A) the inheritance of acquired characteristics
B) sexual selection
C) possession of analogous (convergent) traits
D) possession of shared primitive characters
The pattern of inheritance (monohybrid, dihybrid, sex-linked, and genes linked on the
same chromosomes) can be predicted from data if one is given the parent or offspring
genotypes or phenotypes. Two organisms, with genotypes BbDD and BBDd, are mated.
Assuming independent assortment of the B/b and D/d genes, determine the genotypic
ratios in offspring that would occur.
A) 1/2 BBDD 1/2 bbdd
B) 1/4 BBDD 1/4 BbDD 1/4 BBDd 1/4 BbDd
C) 9/16 BBDD 3/16 BbDD 3/16 BBDd 1/16 bbdd
D) 1/4 BBDD 1/2 BbDd 1/4 bbdd
In eukaryotes, genetic information is passed to the next generation by processes that
include mitosis or meiosis. Which of the explanations identifies the correct process and
supports the claim that heritable information is passed from one generation to another?
A) During mitosis, DNA replication occurs twice within the cell cycle to insure a full
set of chromosomes within each of the daughter cells produced.
B) Mitosis, followed by cytokinesis, produces daughter cells that are genetically
different from the parent cell, thus insuring variation within the population.
C) In asexual reproduction, a single individual is the sole parent and passes copies of its
genes to its offspring without the fusion of gametes.
D) Single-celled organisms can fuse their cells, reproducing asexually through mitosis
to form new cells that are not identical to the parent cell.
Starch and cellulose _____.
A) are polymers of glucose
B) are cis-trans isomers of each other
C) are used for energy storage in plants
D) are structural components of the plant cell wall
What conclusion can you draw from the figure above?
A) Hares control lynx population size.
B) Lynx control hare population size.
C) Lynx and hare populations are independent of each other.
D) The relationship between the populations cannot be determined only from this
graph.
Where is primary growth occurring in an old tree?
A) Nowhere; trees more than a year old have only secondary growth.
B) closest to ground level at the base of the tree
C) in young branches where leaves are forming
D) where the vascular cambium and cork cambium are located
The teacher was unaware of the difference between suspension feeding and predation.
The teacher thought that providing live copepods (2 mm long) and feeder fish (2 cm
long) would satisfy the dietary needs of all of the organisms. Consequently, which two
organisms would have been among the first to starve to death (assuming they lack
photosynthetic endosymbionts)?
A) sponges and corals
B) sea stars and sponges
C) shrimp and bivalves
D) bivalves and sponges
For which of the following is the number the same in spermatogenesis and oogenesis?
A) timing of meiotic divisions
B) functional gametes produced by meiosis
C) meiotic divisions required to produce each gamete
D) different cell types produced by meiosis
Dinoflagellates _____.
A) possess two flagella
B) are all autotrophic
C) lack mitochondria
D) include species that cause malaria