Which figure depicts an animal cell placed in a solution hypotonic to the cell?
A) cell A
B) cell B
C) cell C
D) cell D
A waste product of respiration is
A) electrons.
B) hydrogen peroxide.
C) carbon dioxide.
D) glucose.
What is the main digestive function of the pancreas?
A) to produce digestive enzymes and bile salts
B) to produce digestive enzymes and an alkaline solution
C) to produce bicarbonate-containing mucus
D) to aid in the control of cholesterol
Humans use about ________ of their daily calories to maintain brain cells and power
other life-sustaining activities.
A) 25%
B) 50%
C) 75%
D) 90%
Frequency-dependent selection, as seen in the case of the scale-eating fish in Lake
Tanganyika, tends to
A) eliminate rare alleles and favor whichever allele is initially most frequent.
B) maintain two phenotypes in a dynamic equilibrium in a population.
C) produce random changes in allele frequencies.
D) stimulate new mutations.
To obtain optimal production in a small garden, one should
A) plant seeds in rows with minimal spacing between rows.
B) plant seeds in clumps with large spaces between clumps.
C) plant seeds in a uniform pattern throughout the garden.
D) sow seeds randomly throughout the garden.
You’re conducting an experiment to determine the effect of different wavelengths of
light on the absorption of carbon dioxide as an indicator of the rate of photosynthesis in
aquatic ecosystems. If the rate of photosynthesis increases, the amount of carbon
dioxide in the environment will decrease, and vice versa.
Small aquatic plants are placed into three containers of water mixed with carbon
dioxide. Container A is placed under normal sunlight, B under green light, and C under
red light. The containers are observed for a 24-hour period.
Based on your knowledge of the process of photosynthesis, the plant in the container
placed under red light would probably
A) absorb no CO2.
B) absorb the same amount of CO2 as the plants under the green light.
C) absorb less CO2 than the plants under the green light.
D) absorb more CO2 than the plants under the green light.
An ecological footprint
A) is a means of determining increases in populations that lived in the past.
B) is a means of understanding resource availability and usage.
C) measures dispersion and adaptability.
D) will estimate population movements.
________ are stramenopiles that commonly are found decomposing dead animals in
freshwater habitats.
A) Brown algae
B) Water molds
C) Cellular slime molds
D) Plasmodial slime molds
Invertebrate diversity contributes to all of the following except
A) medicines.
B) food sources for humans.
C) bioremediation.
D) cosmetics.
A protein coat enclosing a viral genome is known as a(n)
A) capsule.
B) envelope.
C) capsid.
D) prophage.
Which of the following is not an observed effect of global warming on organisms?
A) Some species of birds and frogs now begin their breeding seasons later in the year.
B) Corals “bleach” when increased water temperatures cause them to expel their
symbiotic algae.
C) Many butterfly populations have shifted their ranges to the north.
D) Many polar bears show signs of starvation as their hunting grounds melt away.
Much of the intracellular structure of a eukaryote cell is involved in protein synthesis.
The figure shows the amounts of protein in cells at different parts of the cell cycle
between two cell divisions. G1 is a stage just after the cell has divided, and G2 is the
stage just before the cell divides again. S is a stage when the cell is synthesizing
material such as DNA, mitochondria, and other organelles.
Which of the following can be concluded from the graph?
A) There are three times as many cells in G2 as there are in G1.
B) Cells in S have 30% more protein than cells in G1.
C) Cells in G2 have three times as much protein as cells in G1.
D) The same proteins are present at each stage but are present in different amounts.
Mycorrhizal fungi are sometimes purposely introduced to new areas of land that are
used for growing plants for commercial uses (e.g., landscaping, crop production, timber
production). What would be the benefit of doing this?
A) The fungi absorb toxic pesticides from the ground.
B) The fungi help facilitate horticulture, agriculture, and forestry.
C) The fungi promote the evolution of new fungus species.
D) The fungi prevent competitive plant species from growing.
Which stage of the life cycle shown is the sporophyte?
A) stage A
B) stage B
C) stage C
D) stage D
Conjugation between a bacterium that lacks an F factor (F–) and a bacterium that has an
F factor on its chromosome (F+) could produce which of the following results?
A) The F–bacterium ends up carrying one or more plasmids from the F+ bacterium; the
F+ bacterium is unchanged.
B) The F+ bacterium ends up with a recombinant chromosome that carries some genes
from the F– bacterium, and the F–bacterium ends up with an unaltered chromosome.
C) The F+ bacterium ends up with a recombinant chromosome that carries some genes
from the F–bacterium, and the F–bacterium ends up with a chromosome that lacks those
genes.
D) The F–bacterium ends up with a recombinant chromosome that carries some genes
from the F+ bacterium, and the F+ bacterium ends up with an unaltered chromosome.
Which of the following statements regarding chemical reactions is false?
A) Chemical reactions involve the making and breaking of chemical bonds.
B) Some chemical reactions create electrons; others destroy them.
C) The reactants contain the same number of atoms as the products.
D) Although the atoms of a reaction’s reactants and products are identical to each other,
their molecular formulas differ.
Which of the following options best describes the mechanism that causes a stoma to
open?
A) K+ enters the guard cells and water follows passively, making the cells turgid.
B) K+ activates water pumps in the guard cell membrane that make them turgid.
C) K+ leaves the guard cells and water follows passively, making the cells flaccid.
D) Loss of K+ from guard cells creates positive pressure and expands the guard cells.
The brain and sensory system of a bilaterally symmetric organism function most like
A) the engine of a motorboat.
B) the pilot of an airplane.
C) the passengers on a train.
D) a member of a marching band.
Which ocean zone describes the interface between ocean and land?
A) intertidal
B) pelagic
C) abyssal
D) upwelling
One of the finest available sequences of fossils shows how horses have changed slowly
and by subtle steps from small shrub-browsing ancestors to the large, grass-grazing
modern horse. A large number of fossil species have been named, and it is often
difficult to decide on the identity of a fossil horse because transitional forms are
common. The species concept most applicable to these organisms would be
A) the biological species concept.
B) the ecological species concept.
C) the morphological species concept.
D) the phylogenetic species concept.
In the countercurrent exchange system of fish gills,
A) blood and water flow in the same direction.
B) blood and water flow in opposite directions.
C) blood and water are separated by a thick polysaccharide barrier.
D) blood flow in the gills reverses direction with every heartbeat.
Mononucleosis (“mono”) is usually caused by EBV, or the Epstein-Barr virus. Mono is
more common in children than in adults because adults usually have developed
________ toward the virus.
A) innate immunity
B) adaptive immunity
C) lymphocytes
D) passive immunity
Suppose that an elephant with the genotype EEFfggHh reproduces with an elephant
with the genotype eeFFGgHh. What is the probability that a baby elephant (called a
calf) would have the genotype EeFFGghh?
A) 1/16
B) 1/32
C) 1/64
D) 1/256
Uranium is a metallic element that is used in nuclear reactors and nuclear weapons. The
vast majority of uranium found on Earth is in the form of uranium-238, an isotope with
a mass number of 238, while the uranium that is used for nuclear reactors and weapons
is uranium-235, an isotope with a mass number of 235.
What is the atomic difference between uranium-235 and uranium-238?
A) Uranium-235 has three fewer protons than uranium-238.
B) Uranium-235 has three fewer neutrons than uranium-238.
C) Uranium-235 has three fewer electrons than uranium-238.
D) Uranium-235 has three fewer atoms than uranium-238.
Hormones are chemicals produced by the endocrine system that
A) control the formation of urine.
B) regulate a variety of body functions, such as metabolism.
C) are stimulated by the action of metabolic enzymes.
D) function to prevent a variety of diseases, such as diabetes.
The function of chloroplasts is
A) cellular respiration.
B) lipid synthesis.
C) photosynthesis.
D) intracellular digestion.
The acrosome of sperm cells contains an enzyme called hyaluronidase. Which of the
following procedures would benefit from the addition of hyaluronidase?
A) ligating two strands of DNA together
B) helping a drug to pass through a cell membrane
C) assisting with mitotic division of skin cells
D) increasing levels of FSH released from the hypothalamus
Which part of this figure depicting an ear is the cochlea?
A) part A
B) part B
C) part C
D) part D
If a prokaryote is placed in an aquatic environment that has moderate sunlight
availability as well as dead plant material, an effective mode of nutrition would be
A) photoautotrophic behavior.
B) chemotrophic behavior.
C) mixotrophic behavior.
D) chemoautotrophic behavior.
Most fishes can live either in freshwater or in saltwater habitats, but not in both. If you
move a marine fish from the ocean to a lake, it will quickly die, and vice versa.
However, a small number of fish species are capable of moving between the two
environments. Salmon are osmoregulators that hatch in rivers, spend most of their lives
in the ocean, and return to the river where they were born in order to breed.
When a salmon leaves the river and moves out to sea, you would expect ________ to
leave its body by osmosis and that excess ________ would need to be pumped out.
A) salt; water
B) water; salt
C) salt; salt
D) water; water
Typically, nitrogen atoms are composed of electrons, protons, and neutrons. An isotope
of nitrogen could
A) be positively charged.
B) be negatively charged.
C) have more protons than the usual nitrogen atom.
D) have more neutrons than the usual nitrogen atom.