When air temperature exceeds their body temperature, jackrabbits living in hot, arid lands
will
A) dilate the blood vessels in their large ears.
B) constrict the blood vessels in their large ears.
C) increase movements to find a sunny area.
D) bask in a sunny, exposed area.
E) begin involuntary shivering of their skeletal muscles.

B

Which choice best describes a reasonable evolutionary mechanism for animal structures
becoming better suited to specific functions?
A) Animals that eat the most food become the most abundant.
B) Animals that restrict their food intake will become less abundant.
C) Animals with mutations that give rise to effective structures will become more
abundant.
D) Animals with inventions that curtail reproduction will become more abundant.
E) Animals with parents that continually improve their offspringʹs structures will
become more abundant.

C

Evolutionary adaptations that help diverse animals exchange matter with the environment
include
A) gastrovascular activity, two-layered body, and torpedo shape.
B) external respiratory surface, small size, and two-layered body.
C) large volume, long tubular body, and wings.
D) complex internal structures, small size, and large surface area.
E) unbranched internal surface, small size, and thick covering

B

) Similar fusiform body shapes are seen in sharks, penguins, and aquatic mammals because
A) natural selection has no limits when different organisms face the same challenge.
B) respiration through gills is enhanced by having a fusiform shape.
C) the laws of physics constrain the shapes that are possible for aquatic animals that
swim very fast.
D) the fusiform shape is coded by the same gene in all three types of animals.
E) all three types evolved from ancestral forms that fly in the air.

C

Regarding the evolution of specialized animal structures,
A) the environment imposes identical problems on all animals regardless of where they
are found.
B) the evolution of structure in an animal is influenced by its ability to learn.
C) the simplest animals are those with the most recent appearance among the biota.
D) short-term adjustments to environmental changes are often mediated by
physiological organ systems.
E) the most complex animals are the ones with the most ancient evolutionary origin

D

All animals, whether large or small, have
A) an external body surface that is dry.
B) a basic body plan that resembles a two-layered sac.
C) a body surface covered with hair to keep them warm.
D) the ability to enter dormancy when resources become scarce.
E) all of their living cells surrounded by an aqueous medium.

E

) As body size increases in animals, there is
A) a decrease in the surface-to-volume ratio.
B) no further reproduction in aqueous environments.
C) the tendency for larger bodies to be more variable in metabolic rate.
D) an increase in migration to tropical areas.
E) a greater challenge to maintaining body warmth in cold environments.

A

To increase the effectiveness of exchange surfaces in the lungs and in the intestines,
evolutionary pressures have
A) increased the surface area available for exchange.
B) increased the thickness of these linings.
C) increased the number of cell layers.
D) decreased the metabolic rate of the cells in these linings.
E) increased the volume of the cells in these linings.

A

A specialized function shared by the many cells lining the lungs and the lumen of the gut is
A) decreased oxygen demand due to the lack of oxygen in foods.
B) increased exchange surface provided by their membranes.
C) greater numbers of cell organelles contained within their cytoplasm.
D) greater protection due to increased cellular mass.
E) lowered basal metabolic rate due to cooperation between cells.

B

Interstitial fluid
A) is the fluid inside the gastrovascular cavity of Hydra.
B) is the internal environment found inside an animalʹs cells.
C) is composed of blood.
D) provides for the exchange of materials between blood and body cells.
E) is found inside the small intestine.

D

) Multicellular organisms must keep their cells awash in an ʺinternal pondʺ because
A) feedback signals cannot cross through the interstitial fluid.
B) cells need an aqueous medium for the exchange of nutrients, gases, and wastes.
C) this prevents the movement of water due to osmosis.
D) cells need to be protected from nitrogen gas in the atmosphere.
E) terrestrial organisms have not adapted to life in dry environments.

B

Tissues are composed of cells, and tissues functioning together make up
A) organs.
B) membranes.
C) organ systems.
D) organelles.
E) organisms.

A

An exchange surface is in direct contact with the external environment in the
A) lungs.
B) skeletal muscles.
C) liver.
D) heart.
E) brain.

A

The epithelium type with the shortest diffusion distance is
A) simple squamous epithelium.
B) simple cuboidal epithelium.
C) simple columnar epithelium.
D) pseudostratified ciliated columnar epithelium.
E) stratified squamous epithelium.

A

The lining of the smallest tubules in the kidneys is composed of
A) connective tissue.
B) smooth muscle cells.
C) neural tissue.
D) epithelial tissue.
E) adipose tissue.

D

An example of a connective tissue is the
A) skin.
B) nerves.
C) blood.
D) cuboidal epithelium.
E) smooth muscles.

C

) Stratified cuboidal epithelium is composed of
A) several layers of box-like cells.
B) a hierarchical arrangement of flat cells.
C) a tight layer of square cells attached to a basement membrane.
D) an irregularly arranged layer of pillar-like cells.
E) a layer of ciliated, mucus-secreting cells.

A

Connective tissues have
A) many densely-packed cells without an extracellular matrix.
B) a supporting material such as chondroitin sulfate.
C) an epithelial origin.
D) relatively few cells and a large amount of extracellular matrix.
E) the ability to transmit electrochemical impulses.

D

The fibers responsible for the elastic resistance properties of tendons are
A) elastin fibers.
B) fibrin fibers.
C) collagenous fibers.
D) reticular fibers.
E) spindle fibers.

C

If you gently twist your ear lobe it does not remain distorted because it contains
A) collagenous fibers.
B) elastin fibers.
C) reticular fibers.
D) adipose tissue.
E) loose connective tissue.

B

Fibroblasts secrete
A) fats.
B) chondroitin sulfate.
C) interstitial fluids.
D) calcium phosphate for bone.
E) proteins for connective fibers.

E

) Blood is best classified as connective tissue because
A) its cells can be separated from each other by an extracellular matrix.
B) it contains more than one type of cell.
C) it is contained in vessels that ʺconnectʺ different parts of an organismʹs body.
D) its cells can move from place to place.
E) it is found within all the organs of the body

A

Muscles are joined to bones by
A) ligaments.
B) tendons.
C) loose connective tissue.
D) Haversian systems.
E) spindle fibers.

B

With its abundance of collagenous fibers, cartilage is an example of
A) connective tissue.
B) reproductive tissue.
C) nervous tissue.
D) epithelial tissue.
E) adipose tissue.

A

Bones are held together at joints by
A) cartilage.
B) osteons.
C) loose connective tissue.
D) tendons.
E) ligaments.

E

) A matrix of connective tissue is apparent in
A) chondroitin sulfate of cartilage.
B) actin and myosin of muscle.
C) adipose deposits.
D) nervous tissues.
E) spindle-shaped smooth muscle cells.

B

The nucleus of a typical nerve cell is found in the
A) cell body.
B) synaptic terminals.
C) axonal region.
D) dendritic region.
E) synapse.

A

All types of muscle tissue have
A) intercalated discs that allow cells to communicate.
B) striated banding pattern seen under the microscope.
C) cells that lengthen when appropriately stimulated.
D) a response that can be consciously controlled.
E) interactions between actin and myosin.

E

All skeletal muscle fibers are both
A) smooth and involuntary.
B) smooth and unbranched.
C) striated and voluntary.
D) smooth and voluntary.
E) striated and branched.

C

) Cardiac muscle is both
A) striated and branched.
B) striated and unbranched.
C) smooth and voluntary.
D) striated and voluntary.
E) smooth and involuntary

A

The type of muscle tissue associated with internal organs, other than the heart, is
A) skeletal muscle.
B) cardiac muscle.
C) striated muscle.
D) intercalated cells.
E) smooth muscle.

E

Food moves along the digestive tract as the result of contractions by
A) cardiac muscles.
B) smooth muscles.
C) voluntary muscles.
D) striated muscles.
E) skeletal muscles.

B

The cells lining the air sacs in the lungs make up a
A) cuboidal epithelium.
B) simple squamous epithelium.
C) stratified squamous epithelium.
D) pseudostratified ciliated columnar epithelium.
E) simple columnar epithelium.

B

The bodyʹs automatic tendency to maintain a constant internal environment is termed
A) balanced equilibrium.
B) physiological chance.
C) homeostasis.
D) static equilibrium.
E) estivation.

C

An example of a properly functioning homeostatic control system is seen when
A) the core body temperature of a runner rises gradually from 37°C to 45°C.
B) the kidneys excrete salt into the urine when dietary salt levels rise.
C) a blood cell shrinks when placed in a solution of salt and water.
D) the blood pressure increases in response to an increase in blood volume.
E) the level of glucose in the blood is abnormally high whether or not a meal has been
eaten.

B

An example of effectorsʹ roles in homeostatic responses is observable when
A) an increase in body temperature results from shivering.
B) an increase in body temperature results from exercise.
C) the rising sun causes an increase in body temperature in a stationary animal.
D) an increase in body temperature resulting from fever.
E) a decrease in body temperature resulting from shock.

A

Positive feedback has occurred when
A) an increase in blood sugar increases the secretion of a hormone that stores sugar as
glycogen.
B) a decrease in blood sugar increases the secretion of a hormone that converts glycogen
to glucose.
C) a nursing infantʹs sucking increases the secretion of a milk-releasing hormone in the
mother.
D) an increase in calcium concentration increases the secretion of a hormone that stores
calcium in bone.
E) a decrease in blood calcium increases the amount of the hormone that releases
calcium from bone.

C

Positive feedback differs from negative feedback in that
A) positive feedback benefits the organism, whereas negative feedback is detrimental.
B) the effectorʹs response in positive feedback is in the same direction as the initiating
stimulus rather than opposite to it.
C) the effectorʹs response increases some parameter (such as temperature), whereas in
negative feedback it decreases.
D) positive feedback systems have only effectors, whereas negative feedback systems
have only receptors.
E) positive feedback systems have control centers that are lacking in negative feedback
systems.

B

To prepare flight muscles for use on a cool morning, hawkmouth moths
A) relax the muscles completely until after they launch themselves into the air.
B) decrease their standard metabolic rate.
C) rapidly contract and relax these muscles to generate metabolic warmth.
D) walk to shaded areas to avoid direct sunlight.
E) reduce the metabolic rate of the muscles to rest them before flight.

C

An ectotherm is more likely to survive an extended period of food deprivation than would
an equally-sized endotherm because
A) the ectotherm maintains a higher basal metabolic rate.
B) the ectotherm expends more energy/kg body weight than the endotherm.
C) the ectotherm invests little energy in temperature regulation.
D) the ectotherm metabolizes its stored energy more readily than can the endotherm.
E) the ectotherm has greater insulation on its body surface.

C

Humans can lose, but cannot gain, heat through the process of
A) conduction.
B) convection.
C) radiation.
D) evaporation.
E) metabolism

D

An ectothermic organism that has few or no options when it comes to its behavioral ability
to adjust its body temperature is a
A) terrestrial lizard.
B) sea star, a marine invertebrate.
C) bluefin tuna, a predatory fish.
D) hummingbird.
E) honeybee in a hive.

B

An overheated and sick dog has an impaired thermoregulatory response if it
A) increases its evaporative heat loss.
B) decreases its metabolic heat production.
C) increases its body temperature to match the environmental temperature.
D) increases its vasodilation in blood vessels near the skin.
E) relocates itself to a cooler location.

C

Endothermy
A) is a characteristic of most animals.
B) involves production of heat through metabolism.
C) is a term equivalent to ʺcold-blooded.ʺ
D) is only seen in mammals.
E) is only seen in insects.

B

Panting observed in overheated birds and mammals dissipates excess heat by
A) countercurrent exchange.
B) acclimation.
C) vasoconstriction.
D) hibernation.
E) evaporation.

E

An organism that has only behavioral controls over its body temperature is the
A) green frog.
B) penguin.
C) bluefin tuna.
D) house sparrow.
E) gray wolf.

A

Most amphibians and land-dwelling invertebrates
A) are ectothermic organisms.
B) alter their metabolic rate to maintain a constant body temperature of 37°C.
C) have a net loss of heat across a moist body surface, even in direct sun.
D) are thermoconformers only when they are in water.
E) become more active when environmental temperatures drop below 15°C.

A

The temperature-regulating center of vertebrate animals is located in the
A) medulla oblongata.
B) thyroid gland.
C) hypothalamus.
D) subcutaneous layer of the skin.
E) liver.

C

A female Burmese python incubating her eggs warms them using
A) acclimatization.
B) torpor.
C) evaporative cooling.
D) non-shivering thermogenesis.
E) shivering thermogenesis.

E

In mammals this response is known as fever, but it is known to raise body temperature in
other bacterially infected animals, including lizards, fishes, and cockroaches:
A) growth of hair
B) reduced metabolic rate
C) sweating
D) a change in thermostat ʺset-pointʺ
E) decreased thermogenesis

D

What does the difference in temperature between arteries and veins in the gooseʹs legs
indicate?
A) The legs need to be kept cool so that muscles will function well.
B) The feet need to be kept at the same temperature as the abdomen so that the feet do
not freeze in water.
C) Minimizing the temperature difference between the feet and the abdomen means the
goose will lose less heat.
D) The arterial blood is always cooler in the abdomen, compared to its temperature in
the feet of the goose.
E) The gooseʹs feet function well even when their temperature falls below freezing.

C

Near the gooseʹs abdomen, the consequence of this arrangement of the arterial and venous
blood vessels is that
A) the temperature difference between the vessels is minimized by countercurrent
exchange.
B) the venous blood is as cold near the abdomen as it is near the feet.
C) the blood in the feet as the same temperature as the blood in the abdomen.
D) the temperature at the abdomen is less than the temperature at the feet.
E) the goose loses the maximum possible amount of heat to the environment.

A

Ingested foods in snakes are typically digested by
A) biosynthesis.
B) enzymatic hydrolysis.
C) uric acid.
D) chemiosmosis.
E) metabolic heat

B

Seasonal changes in snake activity are explained by which statement?
A) The snake is less active in winter because the food supply is decreased.
B) The snake is less active in winter because it does not need to avoid predators.
C) The snake is more active in summer because that is the period for mating.
D) The snake is more active in summer because it can gain body heat by conduction.
E) The snake is more active in summer as a result of being disturbed by other animals

D

The best time to measure an animalʹs basal metabolic rate is when the animal
A) is resting and has not eaten its first meal of the day.
B) is resting and has just completed its first meal of the day.
C) has recently eaten a sugar-free meal.
D) has not consumed any water for at least 48 hours.
E) has just completed 30 minutes of vigorous exercise.

A

) Standard metabolic rate (SMR) and basal metabolic rate (BMR)
A) are used differently: SMR is measured during exercise, while BMR is measured at
rest.
B) are used to compare metabolic rate between hibernating and non-hibernating states.
C) are both measured across a wide range of temperatures for a given species.
D) are both standard measurements of mammals.
E) are both measured in animals in a resting and fasting state.

E

) For an adult human female, the metabolic ʺcostsʺ of pregnancy and lactation are
A) 100 —125% more than when she was non-pregnant.
B) 30—40% more than when she was non-pregnant.
C) 5—8% more than when she was non-pregnant.
D) 10—20% less than when she was non-pregnant.
E) 30—40% less than when she was non-pregnant.

C

As body size increases among birds,
A) the bodyʹs surface area-to-volume ratio increases.
B) the body temperature increases.
C) the basal metabolic rate (BMR) decreases.
D) the standard metabolic rate (SMR) decreases.
E) the rate of energy use per cell decreases.

E

Among these choices, the least reliable indicator of an animalʹs metabolic rate is the amount
of
A) food eaten in one day.
B) heat generated in one day.
C) oxygen used in mitochondria in one day.
D) carbon dioxide produced in one day.
E) water consumed in one day

E

Deer mice in warm climates and penguins in cold climates differ in their energy budgets in
that
A) deer mice use a greater proportion of their metabolic energy to maintain body
temperature.
B) deer mice use a greater proportion of their metabolic energy to move around.
C) penguins can hibernate, but deer mice cannot.
D) deer mice use a greater proportion of their metabolic energy on activity and
movement.
E) penguins use a greater proportion of their metabolic energy for lactation than do deer
mice

A

During its months-long hibernation, the body temperature of a ground squirrel
A) is held at a constant 37°C.
B) is held at a constant 5°C.
C) varies between 5 and 37°C, depending on the frequency of arousals from hibernation.
D) varies between 5 and 15°C, depending on the external temperature.
E) varies between -5 and +5°C, depending on the external temperature.

C

For a non-hibernating squirrel, the daily expenditure of metabolic energy is
A) usually less than the basal metabolic rate (BMR).
B) always greater than the basal metabolic rate (BMR).
C) constant despite day-to-day changes in ambient temperature.
D) measured only by the distance it has traveled.
E) inversely related to the distance it has traveled.

B

ʺWinter acclimatizationʺ in mammals can include
A) the production of antifreeze compounds within cells.
B) the production of enzymes that have lower temperature optima.
C) hibernation through the season of extreme cold.
D) changing the proportion of saturated and unsaturated fats in cell membranes.
E) the denaturation of proteins that cannot withstand extreme temperature.

C

Hibernation and estivation are both examples of
A) acclimatization.
B) torpor.
C) evaporative cooling.
D) non-shivering thermogenesis.
E) shivering thermogenesis.

B

Panting by an overheated dog is an example of
A) acclimatization.
B) torpor.
C) evaporative cooling.
D) non-shivering thermogenesis.
E) shivering thermogenesis.

C

Metabolism of specialized brown fat depots in certain animals is substantially increased
during
A) acclimatization.
B) torpor.
C) evaporative cooling.
D) non-shivering thermogenesis.
E) shivering thermogenesis.

D

A moth preparing for flight on a cold morning warms its flight muscles via
A) acclimatization.
B) torpor.
C) evaporative cooling.
D) non-shivering thermogenesis.
E) shivering thermogenesis.

E

Compared with a smaller cell, a larger cell of the same shape has
A) less surface area.
B) less surface area per unit of volume.
C) the same surface-to-volume ratio.
D) a smaller average distance between its mitochondria and the external source of
oxygen.
E) a smaller cytoplasm-to-nucleus ratio.

B

The epithelium best adapted for a body surface subject to abrasion is
A) simple squamous.
B) simple cuboidal.
C) simple columnar.
D) stratified columnar.
E) stratified squamous.

E

Which of the following is not an adaptation for reducing the rate of heat exchange between
an animal and its environment?
A) feathers or fur
B) vasoconstriction
C) nonshivering thermogenesis
D) countercurrent heat exchanger
E) blubber or fat layer

C

Which of the following animals uses the highest percent of its energy budget for
homeostatic regulation?
A) a hydra
B) a marine jelly (an invertebrate)
C) a snake in a temperate forest
D) a desert insect
E) a desert bird

E

Consider the energy budgets for a human, an elephant, a penguin, a mouse, and a snake.
The __________ would have the highest total annual energy expenditure, and the
__________ would have the highest energy expenditure per unit mass.
A) elephant; mouse
B) elephant; human
C) human; penguin
D) mouse; snake
E) penguin; mouse

A

An animalʹs inputs of energy and materials would exceed its outputs
A) if the animal is an endotherm, which must always take in more energy because of its
high metabolic rate.
B) if it is actively foraging for food.
C) if it is hibernating.
D) if it is growing and increasing its biomass.
E) never; homeostasis makes these energy and material budgets always balance.

D