Heartwood and sapwood consist of _____.
A) periderm
B) secondary xylem
C) secondary phloem
D) cork
Your friend is wary of environmentalists’ claims that global warming could lead to
major biological change on Earth. Which of the following statements can you use in
response to your friend’s suspicions?
I) We know that atmospheric carbon dioxide has increased over the past 150 years.
II) Through measurements and observations, we know that carbon dioxide levels and
temperature fluctuations are directly correlated, even in prehistoric times.
III) Global warming could have significant effects on agriculture in the United States.
A) only I
B) only II
C) only III
D) I, II, and III
Reproductive cloning of human embryos is generally considered unethical. However,
on the subject of therapeutic cloning there is a wider divergence of opinion. Which of
the following is a likely explanation?
A) The use of adult stem cells is likely to produce more cell types than the use of
embryonic stem cells.
B) Cloning to produce embryonic stem cells may lead to great medical benefits for
many.
C) Cloning to produce stem cells relies on a different initial procedure than
reproductive cloning.
D) A clone that lives until the blastocyst stage does not yet have human DNA.
In a human karyotype, chromosomes are arranged in 23 pairs. If we choose one of these
pairs, such as pair 14, which of the following do the two chromosomes of the pair have
in common?
A) length and position of the centromere only
B) length, centromere position, and staining pattern only
C) length, centromere position, staining pattern, and traits coded for by their genes
D) They have nothing in common except that they are X-shaped.
Which of the following life history traits can potentially influence effective population
size?
I) age of sexual maturation
II) genetic relatedness among individuals in a population
III) family size and population size
IV) gene flow between geographically separated populations
A) only I and III
B) only II and IV
C) only II, III, and IV
D) I, II, III and IV
When an arborist prunes a limb off a valuable tree, he or she may paint the cut surface.
The primary purpose of the paint is to_____.
A) minimize water loss by evaporation from the cut surface
B) improve the appearance of the cut surface
C) stimulate growth of the cork cambium to “heal” the wound
D) block entry of pathogens through the wound
A genetic test to detect predisposition to cancer would likely examine the APC gene for
involvement in which type(s) of cancer?
A) colorectal only
B) lung and breast
C) lung only
D) lung and prostate
The beginning of anaphase is indicated by which of the following?
A) Chromatids lose their kinetochores.
B) Cohesin attaches the sister chromatids to each other.
C) Cohesin is cleaved enzymatically.
D) Spindle microtubules begin to polymerize.
Cells that are infected, damaged, or have reached the end of their functional life span
often undergo “programmed cell death.” This controlled cell suicide is called apoptosis.
Select the appropriate description of this event on a cell’s life cycle.
A) Apoptosis is regulated by cell surface receptors that signal when a cell has reached
its density-dependent limits.
B) During apoptosis, dying cells leak out their contents including digestive enzymes
that also destroy healthy cells.
C) During apoptosis, cellular agents chop up the DNA and fragment the organelles and
other cytoplasmic components of a cell.
D) Each cell organelle has protein signals that initiate the breakdown of the organelle’s
components which leads to cell death.
Which of the following correctly displays the sequence of developmental milestones?
A) blastula → gastrula → cleavage
B) cleavage → gastrula → blastula
C) cleavage → blastula → gastrula
D) gastrula → blastula → cleavage
Refer to the figure above. Which of the following forms a monophyletic group?
A) A, B, C, D
B) C and D
C) D, E, and F
D) E, F, and G
A significant contribution of intestinal bacteria to human nutrition is the benefit of
bacterial _____.
A) production of vitamins A and C
B) absorption of organic materials
C) production of vitamin K
D) recovery of water from fecal matter
The M-phase checkpoint ensures that all chromosomes are attached to the mitotic
spindle. If this does not happen, cells would most likely be arrested in _____.
A) telophase
B) prophase
C) prometaphase
D) metaphase
Apical meristems of dicots are at the tips of stems. Apical meristems of grasses are at
ground level or slightly below, concealed by the leaves. The leaves also have an
intercalary meristem at their bases. What does this mean when considering care of a
lawn or soccer field?
A) If you mow right at ground level, the leaves can keep growing with no problem.
B) Grass mowed two inches above ground level grows at a slower rate compared to
grass mowed three inches above the ground level.
C) If you mow two inches above ground level, most apical meristems will be cut down.
D) If you mow two inches above ground level, both the apical and intercalary
meristems can keep producing new cells.
When a cell is in equilibrium with its environment, which of the following occurs for
substances that can diffuse through the cell?
A) There is random movement of substances into and out of the cell.
B) There is directed movement of substances into and out of the cell.
C) There is no movement of substances into and out of the cell.
D) All movement of molecules is directed by active transport.
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 makes them similar to many angiosperms?
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
Which part of a plant absorbs most of the water and minerals taken up from the soil?
A) root cap
B) root hairs
C) the thick parts of the roots near the base of the stem
D) storage roots
As big as it is, the ocean is nutrient-limited. If you wanted to investigate this
phenomenon, one reasonable approach would be to _____.
A) observe Antarctic Ocean productivity from year to year to see if it changes
B) experimentally enrich some areas of the ocean and compare their productivity to that
of untreated areas
C) compare nutrient concentrations between the photic zone and the benthic zone in
various marine locations
D) contrast nutrient uptake by autotrophs in marine locations that are different
temperatures
When nucleotides polymerize to form a nucleic acid _____.
A) a covalent bond forms between the sugar of one nucleotide and the phosphate of a
second
B) a hydrogen bond forms between the sugar of one nucleotide and the phosphate of a
second
C) covalent bonds form between the bases of two nucleotides
D) hydrogen bonds form between the bases of two nucleotides
Matter is gained or lost in ecosystems. How does this occur?
A) Chemoautotrophic organisms can convert matter to energy.
B) Matter can be moved from one ecosystem to another.
C) Photosynthetic organisms convert solar energy to sugars.
D) Heterotrophs convert heat to energy.
In the figure above, which of the following survivorship curves applies to most plant
species?
A) curve A
B) curve B
C) curve C
Two small, poorly drained lakes lie close to each other in a northern forest. The basins
of both lakes are composed of the same geologic substratum. One lake is surrounded by
a dense Sphagnum mat; the other is not. Compared to the pond with Sphagnum, the
pond lacking the moss mat should have _____.
A) lower numbers of bacteria
B) reduced rates of decomposition
C) reduced oxygen content
D) less-acidic water
Scientists developed a set of guidelines to address the safety of DNA technology. Which
of the following is one of the adopted safety measures?
A) Microorganisms used in recombinant DNA experiments are genetically crippled to
ensure that they cannot survive outside of the laboratory.
B) Genetically modified organisms are not allowed to be part of our food supply.
C) Transgenic plants are engineered so that the plant genes cannot hybridize.
D) Experiments involving HIV or other potentially dangerous viruses have been
banned.
Correns found that the inheritance of variegated color on the leaves of certain plants
was determined only by the maternal parent. What phenomenon explains this pattern?
A) ribosome structure
B) chloroplast inheritance
C) genomic imprinting
D) sex-linkage
Regeneration, the regrowth of lost body parts, normally follows _____.
A) all types of asexual reproduction
B) fission
C) fragmentation
D) parthenogenesis
You discover a rare new bird species, but you are unable to observe its mating behavior.
You see that the male is large and ornamental compared with the female. On this basis,
you can probably conclude that the species is _____.
A) polygamous
B) monogamous
C) polyandrous
D) agonistic
Which of the following assumptions have to be made regarding the mark-recapture
estimate of population size?
I) Marked and unmarked individuals have the same probability of being trapped.
II) The marked individuals have thoroughly mixed with the population after being
marked.
III) No individuals have entered or left the population by immigration or emigration,
and no individuals have been added by birth or eliminated by death during the course of
the estimate.
A) I only
B) II only
C) I and II only
D) I, II, and III
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.
Assuming that the rate of sea-floor spreading was constant during the one-million-year
period depicted above, what should be the approximate age of marine fossils found in
undisturbed sedimentary rock immediately overlying the igneous rock at the arrow
labeled “II”?
A) 10,000 years
B) 250,000 years
C) 500,000 years
D) 1,000,000 years
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
Which of the following is directly related to a single amino acid?
A) the base sequence of the tRNA
B) the amino acetyl tRNA synthase
C) the three-base sequence of mRNA
D) the complementarity of DNA and RNA
The best classification system is that which most closely _____.
A) unites organisms that possess similar morphologies
B) conforms to traditional, Linnaean taxonomic practices
C) reflects evolutionary history
D) reflects the basic separation of prokaryotes from eukaryotes
The atomic number of chlorine is 17. The atomic number of magnesium is 12. What is
the formula for magnesium chloride?
A) MgCl
B) MgCl2
C) Mg2Cl
D) MgCl3