Which one of the atoms shown would be most likely to form a cation with a charge of
+1?
A)
B)
C)
D)
An decrease from pH 7.4 to pH 7.2 causes hemoglobin to _____.
A) release all bound carbon dioxide molecules
B) bind more oxygen molecules
C) increase its binding of H+
D) give up more of its oxygen molecules
Which of the following is the best explanation for the inability of a specific animal cell
to reduce the Ca2+ concentration in its cytosol compared with the extracellular fluid?
A) blockage of the synaptic signal
B) loss of transcription factors
C) insufficient ATP levels in the cytosol
D) low levels of protein kinase in the cell
Which of the following causes populations to shift most quickly from an exponential to
a logistic population growth?
A) favorable climatic conditions
B) removal of predators
C) decreased death rate
D) competition for resources
The higher the proportion of loci that are “fixed” in a population, the lower are that
population’s _____.
A) nucleotide variability
B) chromosome number
C) average heterozygosity
D) nucleotide variability and average heterozygosity
Why do scientists consider HIV to be an emerging virus?
A) HIV infected humans long before the 1980s, but it has now mutated to a more
deadly form.
B) HIV mutates rapidly making the virus very different from HIV in the early 1980s.
C) HIV suddenly became apparent and widespread in the 1980s.
D) HIV is now starting to cause diseases other than AIDS, such as rare types of cancers
and pneumonias.
In a healthy cell, the rate of DNA repair is equal to the rate of DNA mutation. When the
rate of repair lags behind the rate of mutation, what is a possible fate of the cell?
A) The cell can be transformed to a cancerous cell.
B) RNA may be used instead of DNA as inheritance material.
C) The cell will become embryonic.
D) DNA synthesis will continue by a new mechanism.
Short-term memory information processing usually causes changes in the _____.
A) brainstem
B) medulla
C) hypothalamus
D) hippocampus
The arrangement of organs and tissues in their characteristic places in 3-D space defines
_____.
A) pattern formation
B) differentiation
C) determination
D) organogenesis
If in the future the current molecular evidence regarding animal origins is further
substantiated, what will be true of any contrary evidence regarding the origin of animals
derived from the fossil record?
A) The contrary fossil evidence will be seen as a hoax.
B) The fossil evidence will be understood to have been interpreted incorrectly because
it is incomplete.
C) The fossil record will henceforth be ignored.
D) Phylogenies involving even the smallest bit of fossil evidence will need to be
discarded.
A person is most likely to recover from a viral infection if the infected cells _____.
A) can undergo normal cell division
B) can carry on translation, at least for a few hours
C) produce and release viral protein
D) transcribe viral mRNA
Poliovirus is an RNA virus of the picornavirus group, which uses its RNA as mRNA. At
its end, the RNA genome has a viral protein (VPg) instead of a cap. This is
followed by a nontranslated leader sequence, and then a single long protein-coding
region (~7000 nucleotides), followed by a poly-A tail. Observations were made that
used radioactive amino acid analogues. Short period use of the radioactive amino acids
result in labeling of only very long proteins, while longer periods of labeling result in
several different short polypeptides. What conclusion is most consistent with the results
of the radioactive labeling experiment?
A) Host cell ribosomes only translate the viral code into short polypeptides.
B) The RNA is only translated into a single long polypeptide, which is then cleaved into
shorter ones.
C) The RNA is translated into short polypeptides, which are subsequently assembled
into large ones.
D) The large radioactive polypeptides are coded by the host, whereas the short ones are
coded for by the virus.
A given organism has 46 chromosomes in its karyotype. Therefore, we can conclude
that it must _____.
A) be human
B) be an animal
C) reproduce sexually
D) have gametes with 23 chromosomes
Biological evolution of life on Earth, from simple prokaryote-like cells to large,
multicellular eukaryotic organisms, _____.
A) has occurred in accordance with the laws of thermodynamics
B) has caused an increase in the entropy of the planet
C) has been made possible by expending Earth’s energy resources
D) has occurred in accordance with the laws of thermodynamics, by expending Earth’s
energy resources and causing an increase in the entropy of the planet
Unlike eutherians, both monotremes and marsupials _____.
A) lack nipples
B) have some embryonic development outside the uterus
C) lay eggs
D) are found in Australia and Africa
Urea is _____.
A) insoluble in water
B) the primary nitrogenous waste product of humans
C) the primary nitrogenous waste product of most birds
D) the primary nitrogenous waste product of most aquatic invertebrates
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
Broad-spectrum antibiotics inhibit the growth of most intestinal bacteria. Consequently,
assuming that nothing is done to counter the reduction of intestinal bacteria, a hospital
patient who is receiving broad-spectrum antibiotics is most likely to become _____.
A) unable to fix carbon dioxide
B) antibiotic resistant
C) unable to synthesize peptidoglycan
D) deficient in certain vitamins and nutrients
Terrestrial organisms lose water through evaporation. In what ecosystem might an
entomologist find a good study organism to examine the prevention of water loss?
A) wet rain forest
B) desert
C) prairie
D) chaparral
How is natural selection related to sexual reproduction as opposed to asexual
reproduction?
A) Sexual reproduction results in many new gene combinations, some of which will
lead to differential reproduction.
B) Sexual reproduction results in the greatest number of new mutations.
C) Sexual reproduction allows the greatest number of offspring to be produced.
D) Sexual reproduction utilizes far less energy than asexual reproduction.
Starting with a fertilized egg (zygote), a series of five cell divisions would produce an
early embryo with how many cells?
A) 8
B) 16
C) 32
D) 64
FtsZ is a bacterial cytoskeletal protein that forms a contractile ring involved in bacterial
cytokinesis. Its function is analogous to _____.
A) the cleavage furrow of eukaryotic animal cells
B) the cell plate of eukaryotic plant cells
C) the mitotic spindle of eukaryotic cells
D) the microtubule-organizing center of eukaryotic cells
Most of the neurons in the human brain are _____.
A) sensory neurons
B) motor neurons
C) interneurons
D) peripheral neurons
The main cause of the increase in the amount of carbon dioxide in Earth’s atmosphere
over the past 150 years is _____.
A) increased worldwide primary production
B) an increase in the amount of infrared radiation absorbed by the atmosphere
C) the burning of larger amounts of wood and fossil fuels
D) additional respiration by the rapidly growing human population
Put the following events of elongation in prokaryotic translation in chronological order.
1. Binding of mRNA with small ribosomal subunit
2. Recognition of initiation codon
3. Complementary base pairing between initiator codon and anticodon of initiator tRNA
4. Base pairing of the mRNA codon following the initiator codon with its
complementary tRNA
5. Attachment of the large subunit
A) 1, 2, 3, 4, 5
B) 2, 1, 4, 3, 5
C) 5, 4, 3, 2, 1
D) 1, 2, 3, 5, 4
The point of connection between two communicating neurons is called the _____.
A) axon hillock
B) dendrite
C) synapse
D) glia
Refer to the following figure, which diagrams the reproductive anatomy of the human
male, to answer the question(s) below.
In the above figure, which letter points to the vas deferens?
A) A
B) B
C) C
D) D
The motor (somatic nervous) system can alter the activities of its targets, the skeletal
muscle fibers, because _____.
A) it is electrically coupled by gap junctions to the muscles
B) its signals bind to receptor proteins on the muscles
C) its signals reach the muscles via the blood
D) it is connected to the internal neural network of the muscles
Which of the following are water-conducting cells that are dead at functional maturity?
A) parenchyma cells
B) collenchyma cells
C) tracheids and vessel elements
D) sieve-tube elements
The cyclin component of MPF is destroyed toward the end of which phase?
A) G1
B) S
C) G2
D) M
Why is the climate drier on the leeward (downwind) side of mountain ranges that are
subjected to prevailing winds?
A) Deserts create dry conditions on the leeward side of mountain ranges.
B) The sun illuminates the leeward side of mountain ranges at a more direct angle,
converting to heat energy, which evaporates most of the water present.
C) Pushed by the prevailing winds on the windward side, air is forced to rise, cool,
condense, and drop its precipitation, leaving drier air to descend the leeward side.
D) Air masses pushed by the prevailing winds are stopped by mountain ranges and the
moisture is used up in the stagnant air masses on the leeward side.
Hydrophobic substances such as vegetable oil are _____.
A) nonpolar substances that repel water molecules
B) nonpolar substances that have an attraction for water molecules
C) polar substances that repel water molecules
D) polar substances that have an affinity for water
Altering patterns of gene expression in prokaryotes would most likely serve an
organism’s survival by _____.
A) organizing gene expression, so that genes are expressed in a given order
B) allowing each gene to be expressed an equal number of times
C) allowing an organism to adjust to changes in environmental conditions
D) allowing environmental changes to alter a prokaryote’s genome