You are cleaning out an old lab freezer and find a tube that contains the ground-up
remains of an unknown animal. Your research advisor suggests that you perform
chemical assays to determine what molecules made up the animal. After analyzing the
data, you determine that the animal contained a large amount of chitin. What type of
animal was in the tube?
A) leech
B) octopus
C) snake
D) lobster
Evolutionary movement of aquatic vertebrates to land involved an intermediate
individual that
A) could fly.
B) had a single lung.
C) had a tracheal system of branching internal tubes.
D) had both gills and lungs.
Plasma membranes are selectively permeable. This means that
A) anything can pass into or out of a cell as long as the membrane is intact and the cell
is healthy.
B) the plasma membrane allows some substances to enter or leave a cell more easily
than others.
C) glucose cannot enter the cell.
D) plasma membranes must be very thick.
If you place an organism classified as a photoautotroph at the bottom of a lake and later
see that it is able to acquire nutrients from dead plant material, you can conclude the
photoautotroph is actually a
A) photoheterotroph.
B) chemoautotroph.
C) chemoheterotroph.
D) mixotroph.
A technique called flow cytometry is used by scientists and researchers to count or sort
cells based on specific properties. By labeling cellular DNA with a fluorescent dye,
flow cytometry can sort cells based on the amount of DNA present, thereby making it
possible to distinguish between cells that are in different stages of the cell cycle. Flow
cytometry is especially useful to the medical community because it can help with the
diagnosis of certain types of cancers.
Below is a typical set of data that you might obtain when running a flow cytometry
experiment using a sample of healthy skin cells. Use this figure to help you answer the
following questions.
If you used flow cytometry to sort a sample of cancerous cells that have been treated
with a drug to prevent them from replicating their DNA, what peaks would you expect
to see on the resulting flow cytometry data set?
A) A only
B) C only
C) A and B only
D) A, B, and C
If you travel through Ecuador from west to east, you will pass through tundra, taiga,
temperate forest, and tropical forest. Which of the following climatic factors remains
constant on such a trip?
A) maximum temperature
B) average rainfall
C) soil type
D) day length
After reading the paragraph below, answer the questions that follow.
Malnutrition can cause a variety of health problems, including being underweight, due
to unbalanced or insufficient diet. It is estimated that in 2015, approximately 14% of
preschool-age children globally will be underweight (WHO and UNICEF Joint Global
Nutrition Database, 2011). While this is a high percentage, it is a drop from
approximately 25% just 25 years earlier.
Consider the data table below and answer the questions that follow.
The data for the developed countries category indicate that developed countries (e.g.,
the United States) have the lowest estimated prevalence (%) of underweight preschool
children from 1990 to 2015. However, what is concerning about these data?
A) There is little variation in estimated prevalence (%) of underweight preschool
children from 1990 to 2015.
B) These are the only data provided that show an increase in estimated prevalence (%)
of underweight preschool children from 1990 to 2015.
C) The estimated prevalence (%) of underweight preschool children is very similar in
year 1995 and year 2000.
D) The estimated prevalence (%) of underweight preschool children from 1990 to 2015
is only slightly below the data for the Caribbean region.
What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons?
A) 6
B) 8
C) 12
D) 18
Which of the following is a way that plants use animals as a defense against herbivores?
A) production of an amino acid that harms herbivores
B) attraction of wasps that kill herbivorous caterpillars
C) release of microbe-killing chemicals in response to infection
D) coevolution between plants and predators
________ are weak bonds that are not strong enough to hold atoms together to form
molecules but are strong enough to form bonds within and around large molecules.
A) Ionic bonds
B) Covalent bonds
C) Polar covalent bonds
D) Hydrogen bonds
A male turkey that imprinted onto a human at hatching is transferred as an older
juvenile to a flock of “normal” turkeys. When this turkey reaches sexual maturity, he
will probably try to court
A) male, female, or immature turkeys indiscriminately.
B) immature male turkeys.
C) mature female turkeys.
D) humans.
After reading the paragraphs below, answer the questions that follow.
Corals belong to phylum Cnidaria. The reefs themselves are made up of millions of
polyps, each of which secretes a calcium carbonate skeleton that becomes part of the
reef structure. Corals, which are attached to the reef as adults, have free-swimming
larvae that develop into new polyps.
Corals are actually colorless. The brilliant colors that are visible on the reef come from
the zooxanthellae (microscopic algae) that live within their body tissues. The
zooxanthellae and corals have a symbiotic relationship in which corals provide carbon
dioxide and mineral nutrients (released as wastes from coral digestion) to the
zooxanthellae. The zooxanthellae perform photosynthesis. Photosynthesis produces
nutrients (in the form of sugars) for the coral and also releases oxygen. This relationship
supplements energy from predation and allows corals to survive in clear tropical water,
even though these areas have very low nutrient levels.
What advantage do free-swimming larvae confer on reef-building corals?
A) providing reef-building corals with a defense against fishes and other predators
B) allowing reef-building corals to establish colonies in the deep ocean
C) increasing survival since coral larvae have exoskeletons of chitin
D) allowing reef-building corals to expand their populations into new habitats
Microfilaments differ from microtubules in that microfilaments
A) are thicker than microtubules.
B) are found only in plants, whereas microtubules are found in both plant and animal
cells.
C) are mainly composed of actin, whereas microtubules are composed of tubulin.
D) help to anchor organelles, whereas microtubules primarily function to help cells
change shape and move.
Flowers bear seeds that develop from ovules housed in protective chambers called
A) stamens.
B) sepals.
C) ovaries.
D) antheridia.
A rabbit population consists of animals that are either very dark on top or very light on
top. The color pattern is not related to sex. No rabbit shows intermediate coloration
(medium darkness). This pattern might result from
A) disruptive selection.
B) directional selection.
C) stabilizing selection.
D) sexual selection.
The hominin group includes ________.
A) Homo sapiens only
B) Homo sapiens and several extinct human relatives.
C) humans and all other apes.
D) all anthropoids.
Baby bobcats watched as their mother stalked a rabbit and pounced, catching a meal
that was shared by all. The next day, two of the young bobcats were seen stalking a
field mouse, which easily escaped from the inexperienced hunters. The young bobcats
were learning how to hunt by the process of
A) social learning.
B) imprinting.
C) habituation.
D) associative learning.
Ferns and mosses are similar because both
A) produce drought-resistant seeds.
B) have dominant sporophytes.
C) have flagellated sperm.
D) have sporophytes that produce diploid spores.
Plantcells treated with auxin would not be able to enlarge under which of the following
conditions?
A) lack of light for growing
B) presence of other hormonesin the plant
C) absence of lysosomes in the plant cells
D) inability of the cell to take up water
Non-native species that are introduced to new environments, spread far beyond the
original point of introduction, and cause damage are called
A) destructive species.
B) enemy species.
C) invasive species.
D) proprietary species.
Which of the following are found in the interstitial fluid and consume any bacteria and
virus-infected cells they encounter?
A) erythrocytes
B) leukocytes
C) macrophages
D) interferons
You are trying to determine the linkage map of a series of genes, X, Y, and Z, from
Caenorhabditis elegans, a nematode worm commonly used in scientific research. From
doing several crossover experiments, you know that the recombination frequency
between X and Y is 11.5%, between Y and Z is 13%, and between X and Z is 25%.
What is a possible sequence of these genes?
A) X-Z-Y
B) Y-Z-X
C) Z-X-Y
D) X-Y-Z
Introduced species are a problem all over the world, and there are many examples in the
United States. Several years ago, a fisherman caught a northern snakehead fish in a
pond in Crofton, Maryland (a suburb of Washington, DC). Snakeheads are a favorite
food of immigrants from China, and live fish can frequently be found in Asian markets.
It was suspected that the fish in the Crofton pond were purchased locally and then
intentionally released.
Snakeheads are top predators, and 90% of the northern snakeheads’ diet consists of
other fishes. The northern snakehead can breathe out of water and travel short distances
(about 100 feet) across land. They also breed rapidly. Females can lay more than
100,000 eggs per year. Juveniles have also been identified in the Potomac River and
other rivers in Pennsylvania.
When snakeheads enter aquatic ecosystems, biodiversity in these ecosystems would
most likely
A) increase, since another species has been added to the environment.
B) decrease, since the snakehead will prey on native species.
C) remain the same, since local species will prey on the snakeheads and remove them.
D) remain the same, because the snakeheads will merge without problems into
established communities.
Cats normally have a total of 18 toes, 5 on each front paw and 4 on each back paw. But
some cats express the dominant phenotype for polydactyly, which results in the
development of extra toes on one or more paws. Jake, a Canadian tabby cat, has 28 toes
and is recognized by the Guinness Book of World Records as the cat with the most toes.
Suppose that Jake mates with a female cat, Lucy, who has 18 total toes. Over several
years, they have multiple litters and a total of 16 kittens (10 males and 6 females). The
total number of toes on each kitten ranges from 21 to 25.
If we use the letter P to represent the polydactyly gene, what is Jake’s genotype?
A) PP
B) Pp
C) pp
D) You cannot determine Jake’s genotype from this information.
When an antigen-presenting cell interacts successfully with a helper T cell, the
antigen-presenting cell secretes a signal molecule that assists in the activation of the
helper T cell. This signal molecule is
A) interferon.
B) complement.
C) interleukin-1.
D) perforin.
Rotenone is a poison commonly added to insecticides. Rotenone binds tightly with one
of the electron carrier molecules in the electron transport chain, preventing electrons
from passing to the next carrier molecule. Insects exposed to rotenone will die because
A) they will no longer be able to perform anaerobic respiration.
B) high levels of fermentation products will build up in their bodies.
C) they will no longer be able to produce adequate amounts of ATP.
D) they will no longer be able to absorb water and will become dehydrated.
One type of virus that infects bacteria is called a
A) phage.
B) retrovirus.
C) rhinovirus.
D) coronavirus.
High levels of which of the following hormones can suppress the body’s immune
system?
A) glucagon
B) mineralocorticoids
C) glucocorticoids
D) antidiuretic hormone
In protostomes,
A) the opening formed during gastrulation becomes the mouth.
B) the opening formed during gastrulation becomes the anus.
C) there is no body cavity.
D) there is no endoderm.
The use of prokaryotes and other organisms to clean up pollutants from soil, air, or
water is called ________.
A) decomposition
B) nitrogen fixation
C) bioremediation
D) biocomposting
A maple tree’s seeds occur in pairs that are enclosed and attached to flat “wings” that
are made of a papery tissue. The wings’ shape allows them to spin in the air as they fall
from the tree; this unusual motion has earned them the nickname “helicopter seeds.”
Maple tree seeds are most successful when they are dispersed by ________.
A) wind
B) water
C) animal feces
D) bird feces
A population is
A) a group of individuals of the same species that live in the same area and interbreed.
B) all individuals of a species, regardless of location or time period in which they live.
C) a group of individuals of different species living in the same place at the same time.
D) a group of individuals of a species plus all of the other species with which they
interact.