Starting from a single individual, what is the size of a population of bacteria at the end
of a two-hour time period if they reproduce by binary fission every twenty minutes?
(Assume unlimited resources and no mortality.)
A) 16
B) 32
C) 64
D) 128
A researcher has used in vitro mutagenesis to mutate a cloned gene and then has
reinserted the mutated gene into a cell. To have the mutated sequence disable the
function of the gene, what must then occur?
A) recombination resulting in replacement of the wild type with the mutated gene
B) use of a microarray to verify continued expression of the original gene
C) replication of the cloned gene using a bacterial plasmid
D) transcription of the cloned gene using a BAC
The leading and the lagging strands differ in that _____.
A) the leading strand is synthesized in the same direction as the movement of the
replication fork, and the lagging strand is synthesized in the opposite direction
B) the leading strand is synthesized by adding nucleotides to the end of the growing
strand, and the lagging strand is synthesized by adding nucleotides to the end
C) the lagging strand is synthesized continuously, whereas the leading strand is
synthesized in short fragments that are ultimately stitched together
D) the leading strand is synthesized at twice the rate of the lagging strand
The molecule illustrated in the accompanying figure _____.
A) is a saturated fatty acid.
B) stores genetic information.
C) will be liquid at room temperature.
D) is a carbohydrate.
After drinking alcoholic beverages, increased urine excretion is the result of _____.
A) increased aldosterone production
B) increased blood pressure
C) inhibited secretion of antidiuretic hormone (ADH)
D) increased reabsorption of water in the proximal tubule
Evidence of which structure or characteristic would be most surprising to find among
fossils of the Ediacaran fauna?
A) true tissues
B) hard parts
C) bilateral symmetry
D) embryos
Compared to a hydrocarbon chain where all the carbon atoms are linked by single
bonds, a hydrocarbon chain with the same number of carbon atoms, but with one or
more double bonds, will _____.
A) be more flexible in structure
B) be more constrained in structure
C) be more polar
D) have more hydrogen atoms
How do we describe transformation in bacteria?
A) the creation of a strand of DNA from an RNA molecule
B) the creation of a strand of RNA from a DNA molecule
C) the infection of cells by a phage DNA molecule
D) assimilation of external DNA into a cell
Which of the following processes includes all others?
A) osmosis
B) facilitated diffusion
C) passive transport
D) transport of an ion down its electrochemical gradient
Testosterone and estradiol are male and female sex hormones, respectively, in many
vertebrates. In what way(s) do these molecules differ from each other? Testosterone and
estradiol _____.
A) are structural isomers but have the same molecular formula
B) are cis-trans isomers but have the same molecular formula
C) have different functional groups attached to the same carbon skeleton
D) are enantiomers of the same organic molecule
In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes.
In the western United States, pronghorns and cattle often associate with one another in
the same open rangeland. Some of these fleas develop a strong preference for cattle
blood and mate only with other fleas that prefer cattle blood. The host mammal can be
considered as the fleas’ habitat. If this situation persists, and new species evolve, this
would be an example of _____.
A) sympatric speciation and habitat isolation
B) sympatric speciation and temporal isolation
C) allopatric speciation and habitat isolation
D) allopatric speciation and gametic isolation
Which of the following best describes a model organism?
A) It is often pictured in textbooks and easy for students to imagine.
B) It is well studied, it is easy to grow, and results are widely applicable.
C) It is small, inexpensive to raise, and lives a long time.
D) It has been chosen for study by early biologists.
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
Chitin is a major component of the _____.
A) skeleton of mammals
B) hydrostatic skeletons of earthworms
C) exoskeleton of insects
D) body hairs of mammals
The voltage across a membrane is called the _____.
A) chemical gradient
B) membrane potential
C) osmotic potential
D) electrochemical gradient
The agouti is most directly involved with the Brazil nut tree’s dispersal of _____.
A) male gametophytes
B) female gametophytes
C) sporophyte embryos
D) sporophyte megaspores
A major function of magnesium in plants is to be _____.
A) required to regenerate phosphoenolpyruvate in C4 and CAM plants
B) a component of DNA and RNA
C) a component of chlorophyll
D) active in amino acid formation
A farm pond, usually dry during winter, has plenty of water and aquatic pond life
during the summer. One summer, Sarah returns to the family farm from college.
Observing the pond, she is fascinated by some six-legged organisms that can crawl
about on submerged surfaces or, when disturbed, seemingly “jet” through the water.
Watching further, she is able to conclude that the “mystery organisms” are ambush
predators, and their prey includes everything from insects to small fish and tadpoles.
Sarah observed that the mystery pond organisms never come up to the pond’s surface. If
she catches one of these organisms and observes closely, perhaps dissecting the
organism, she should find _____.
A) gills
B) spiracles
C) tracheae
D) book lungs
T cells of the immune system include _____.
A) CD4, CD8, and plasma cells
B) cytotoxic and helper cells
C) plasma, antigen-presenting, and memory cells
D) lymphocytes, macrophages, and dendritic cells
Suppose that a group of male pied flycatchers migrated from a region where there were
no collared flycatchers to a region where both species were present. Assuming events
like this are very rare, which of the following scenarios is LEAST likely?
A) Migrant pied males would produce fewer offspring than would resident pied males.
B) Pied females would rarely mate with collared males.
C) Migrant males would mate with collared females more often than with pied females.
D) The frequency of hybrid offspring would decrease.
During elongation, which site in the ribosome represents the location where a codon is
being read?
A) E site
B) P site
C) A site
D) the small ribosomal subunit
What is the term used for a protein molecule that assists in the proper folding of other
proteins?
A) tertiary protein
B) chaperonin
C) renaturing protein
D) denaturing protein
What happens if twice as many inhibitory postsynaptic potentials (IPSPs) as excitatory
postsynaptic potentials (EPSPs) arrive at a postsynaptic neuron in close proximity?
A) A stronger action potential results.
B) A weaker action potential results.
C) No action potential results.
Recombination between linked genes comes about for what reason?
A) Nonrecombinant chromosomes break and then rejoin with one another.
B) Independent assortment sometimes fails.
C) Linked genes travel together at anaphase.
D) Crossovers between these genes result in chromosomal exchange.
The evolution of eukaryotic cells most likely involved _____.
A) endosymbiosis of an aerobic bacterium in a larger host cellthe endosymbiont
evolved into mitochondria
B) anaerobic archaea taking up residence inside a larger bacterial host cell to escape
toxic oxygenthe anaerobic bacterium evolved into chloroplasts
C) an endosymbiotic fungal cell evolving into the nucleus
D) acquisition of an endomembrane system and subsequent evolution of mitochondria
from a portion of the Golgi
Which of the following is released by platelets in the vicinity of an injury?
A) PDGF
B) MPF
C) cyclin
D) Cdk
Soil leaching can cause nutrient deficiencies in the soil. Which of the following are
symptoms of nutrient deficiency in plants?
I) chlorosis
II) death of meristems
III) excess storage of chlorophyll
IV) small internodes
A) I, II, and III
B) II, III, and IV
C) I, II, and IV
D) I, II, III, and IV
In 2008, the population of New Zealand was approximately 4,275,000 people. If the
birth rate was 14 births for every 1000 people, approximately how many births occurred
in New Zealand in 2008?
A) 6,000
B) 42,275
C) 60,000
D) 140,000
Suppose, while out camping in a forest, you found a chordate with a long, slender,
limbless body slithering across the ground near your tent. This critter could be _____.
A) a lampreys
B) a mammal
C) an amphibian
D) a skate
Use the survivorship curves in the figure below to answer the following questions.
Refer to the figure above. Which curve best describes survivorship in elephants?
A) A
B) B
C) C
D) E