What determines whether a carbon atom’s covalent bonds to other atoms are in a
tetrahedral configuration or a planar configuration?
A) the presence or absence of bonds with oxygen atoms
B) the presence or absence of double bonds between the carbon atom and other atoms
C) the polarity of the covalent bonds between carbon and other atoms
D) the solvent in which the organic molecule is dissolved
The questions below refer to the following description and figure.
The figure below represents a cross section of the sea floor through a mid-ocean rift
valley, with alternating patches of black and white indicating sea floor with reversed
magnetic polarities. At the arrow labeled “I” (the rift valley), the igneous rock of the sea
floor is so young that it can be accurately dated using carbon-14 dating. At the arrow
labeled “III,” however, the igneous rock is about one million years old, and
potassium-40 dating is typically used to date such rocks. Note: The horizontal arrows
indicate the direction of sea-floor spreading, away from the rift valley.
How many other bands of sea-floor crust in the figure above have the same magnetic
polarity as the crust that directly straddles the rift valley?
A) two bands
B) four bands
C) five bands
D) eight bands
Cells transplanted from the neural tube of a frog embryo to the ventral part of another
embryo develop into nervous system tissues. This result indicates that the transplanted
cells were _____.
A) totipotent
B) determined
C) differentiated
D) mesenchymal
Imagine that a woman is in the final week of her pregnancy. Her doctor gives her an
injection of oxytocin. The likely result of this is that the pregnant woman would _____.
A) stop secreting prostaglandins from the placenta
B) undergo vigorous contractions of her uterine muscles
C) increase the synthesis and secretion of progesterone
D) be prevented from lactation
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 distinguishes them from most other gymnosperms?
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
The label on a container of margarine lists “hydrogenated vegetable oil” as the major
ingredient. Hydrogenated vegetable oil _____.
A) is solid at room temperature
B) has more “kinks” in the fatty acid chains
C) has fewer trans fatty acids
D) is less likely to clog arteries
Use the figure below to answer the following question.
Which enzyme was used to produce the molecule in the figure above?
A) ligase
B) a restriction enzyme (endonuclease)
C) RNA polymerase
D) DNA polymerase
The same bees that pollinate the flowers of the Brazil nut trees also pollinate orchids,
which are epiphytes (in other words, plants that grow on other plants); however, orchids
cannot grow on Brazil nut trees. These observations explain _____.
A) the coevolution of Brazil nut trees and orchids
B) why Brazil nut trees do not set fruit in monoculture plantations
C) why male orchid bees do not pollinate Brazil nut tree flowers
D) why male orchid bees are smaller than female orchid bees
B cells interacting with helper T cells are stimulated to differentiate when _____.
A) B cells produce IgE antibodies
B) B cells release cytokines
C) cytotoxic T cells present the class II MHC molecule-antigen complex on their
surface
D) helper T cells release cytokines
Leaf thickness represents a trade-off between _____.
A) light collection and carbon dioxide absorption
B) water retention and carbon dioxide absorption
C) water retention and oxygen absorption
D) light collection and oxygenabsorption
Examine the digestive system structures in the figure above. Most of the digestion of
fats occurs in structure(s) _____.
A) 3 only
B) 4 only
C) 1 and 4
D) 3 and 4
Which of the following is the best definition of autoimmune disease?
A) a condition in which B cells and T cells respond independently to antigens and do
not interact correctly
B) a condition in which the adaptive immune system fails to recognize the second
infection by the same antigen
C) a condition in which self molecules are treated as non-self
D) a condition in which the immune system creates random antibodies without being
triggered by an antigen
Which of the pairs of molecular structures shown below depict enantiomers
(enantiomeric forms) of the same molecule?
A)
B)
C)
D)
In the digestive system, peristalsis is _____.
A) a process of fat emulsification in the small intestine
B) voluntary control of the rectal sphincters regulating defecation
C) the transport of nutrients to the liver through the hepatic portal vessel
D) smooth muscle contractions that move food along the esophagus
Which of the following mechanisms are used to regulate blood pressure in the closed
circulatory system of vertebrates?
I) changing the force of heart contraction
II) constricting and relaxing sphincters in the walls of arterioles
III) adjusting the volume of blood contained in the veins
A) only I and II
B) only I and III
C) only II and III
D) I, II, and III
Cyclin-dependent kinase (Cdk) is _____.
A) inactive, or “turned off,” in the presence of cyclin
B) present only during the S phase of the cell cycle
C) the enzyme that catalyzes the attachment of chromosomes to microtubules
D) an enzyme that attaches phosphate groups to other proteins
The hormone that stimulates the production of red blood cells, and the organ where this
hormone is synthesized, are _____.
A) growth hormone and pancreas, respectively
B) erythropoietin and kidney, respectively
C) cortisol and adrenal gland, respectively
D) acetylcholine and bone marrow, respectively
Choose the term that matches the description. This is caused by excessive nutrient
runoff into aquatic ecosystems.
A) depletion of ozone layer
B) acid precipitation
C) biological magnification
D) eutrophication
Which of the following is responsible for the differences in summer and winter
temperature stratification of deep temperate zone lakes?
A) Water is densest at 4C.
B) Oxygen is most abundant in deeper waters.
C) Winter ice sinks in the summer.
D) Stratification is caused by a thermocline.
To maintain homeostasis freshwater fish must _____.
A) excrete large quantities of electrolytes
B) consume large quantities of water
C) excrete large quantities of water
D) take in electrolytes through simple diffusion
Gray seed color in peas is dominant to white. Assume that Mendel conducted a series of
experiments where plants with gray seeds were crossed among themselves, and the
following progeny were produced: 302 gray and 98 white.
(a) What is the most probable genotype of each parent?
(b) Based on your answer in (a) above, what genotypic and phenotypic ratios are
expected in these progeny? (Assume the following symbols: G = gray and g = white.)
A) (a) GG gg; (b) genotypic = 3:1, phenotypic = 1:2:1
B) (a) Gg Gg; (b) genotypic = 1:2:1, phenotypic = 3:1
C) (a) GG Gg; (b) genotypic = 1:2:1, phenotypic = 2:1
D) (a) gg Gg; (b) genotypic = 1:2, phenotypic = 3:1
How did the evolution of the jaw contribute to diversification of early vertebrate
lineages?
A) It allowed for smaller body size.
B) It was the first stage in the development of a bony skull.
C) It made additional food sources available.
D) It increased the surface area for respiration and feeding.
Most types of communication between cells utilize _____.
A) the exchange of cytosol between the cells
B) the movement of the cells
C) chemical or electrical signals
D) the exchange of DNA between the cells
Which of the following pairs of protists and their characteristics is mismatched?
A) apicomplexans internal parasites
B) euglenozoans unicellular flagellates
C) ciliates red tide organisms
D) entamoebas ingestive heterotrophs
The partial negative charge in a molecule of water occurs because _____.
A) the oxygen atom donates an electron to each of the hydrogen atoms
B) the electrons shared between the oxygen and hydrogen atoms spend more time
around the oxygen atom nucleus than around the hydrogen atom nucleus
C) the oxygen atom has two pairs of electrons in its valence shell that are not
neutralized by hydrogen atoms
D) one of the hydrogen atoms donates an electron to the oxygen atom
Cotton-topped tamarins are small primates with tufts of long white hair on their heads.
While studying these creatures, you notice that males with longer hair get more
opportunities to mate and father more offspring. To test the hypothesis that having
longer hair is adaptive in these males, you should _____.
A) test whether other traits in these males are also adaptive
B) look for evidence of hair in ancestors of tamarins
C) determine if hair length is heritable
D) test whether males with shaved heads are still able to mate
How are two different species most likely to evolve from one ancestral species?
A) sympatrically, by a point mutation affecting morphology or behavior
B) sympatrically, due to extensive inbreeding
C) allopatrically, due to extensive inbreeding
D) allopatrically, after the ancestral species has split into two populations
Many species of snakes lay eggs. However, in the forests of northern Minnesota, where
growing seasons are short, only live-bearing snake species are present. This trend
toward species that have live birth in a particular environment is an example of _____.
A) an exaptation
B) sexual selection
C) species selection
D) goal direction in evolution
Through a microscope, you can see a cell plate beginning to develop across the middle
of a cell and nuclei forming on either side of the cell plate. This cell is most likely
_____.
A) an animal cell in the process of cytokinesis
B) a plant cell in the process of cytokinesis
C) an animal cell in the S phase of the cell cycle
D) a plant cell in metaphase
Which of the following statements about action potentials is correct?
A) Action potentials for a given neuron vary in magnitude.
B) Action potentials for a given neuron vary in duration.
C) Action potentials are propagated down the length of the axon.
D) Movement of ions during the action potential occurs mostly through the sodium
pump.
The evolution of similar insulating skin coverings such as fur, hair, and feathers in
mammals and birds is a result of _____.
A) shared ancestry
B) convergent evolution
C) homology
D) evolutionary divergence
The following experiment is used for the corresponding question(s).
A researcher discovered a species of moth that lays its eggs on oak trees. Eggs are laid
at two distinct times of the year: early in spring when the oak trees are flowering and in
midsummer when flowering is past. Caterpillars from eggs that hatch in spring feed on
oak flowers and look like oak flowers. But caterpillars that hatch in summer feed on
oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on
the same trees? To answer this question, the biologist caught many female moths from
the same population and collected their eggs. He put at least one egg from each female
into eight identical cups. The eggs hatched, and at least two larvae from each female
were maintained in one of the four temperature and light conditions listed below.
In each of the four environments, one of the caterpillars was fed oak flowers, the other
oak leaves. Thus, there were a total of eight treatment groups (4 environments 2 diets).
Refer to the accompanying figure. In every case, caterpillars that feed on oak flowers
look like oak flowers. In every case, caterpillars that were raised on oak leaves looked
like twigs. These results support which of the following hypotheses?
A) The longer day lengths of summer trigger the development of twig-like caterpillars.
B) Differences in air pressure, due to elevation, trigger the development of different
types of caterpillars.
C) Differences in diet trigger the development of different types of caterpillars.
D) The differences are genetic. A female will either produce all flowerlike caterpillars
or all twig-like caterpillars.
Which trophic level is most vulnerable to extinction?
A) producer level
B) primary consumer level
C) secondary consumer level
D) tertiary consumer level