|
Which of the following is a correct statement about an organism and its environment?
The interstitial fluid is the exchange medium between body cells and the circulatory system in vertebrate animals.
Animals isolated from their environments live longer than those exchanging matter with the environment.
An animal is a closed system that is separate and distinct from its environment.
The gastrovascular cavity provides the nutrient exchange surface in mammals.
None of the choices is correct.
|
The interstitial fluid is the exchange medium between body cells and the circulatory system in vertebrate animals.
|
|
The four major categories of tissues are _____.
simple squamous, simple cuboidal, simple columnar, and stratified squamous
blood, nervous, connective, and muscle
muscle, epithelial, bone, and cartilage
nervous, epithelial, connective, and muscle
bone, muscle, blood, and adipose
|
nervous, epithelial, connective, and muscle
|
|
Homeostasis is the _____.
maintenance of a relatively constant and optimal internal environment
correlation of structure and function
cooperation of body parts to form tissues, organs, and systems
exchange of materials with the surrounding environment
idea that all vertebrates are built in a similar way
|
maintenance of a relatively constant and optimal internal environment
|
|
Negative feedback is a method of homeostatic control that _____.
increases the speed and rapidity of negative responses to environmental stimuli
ensures that conditions in an organism do not vary too much above or below their set points
operates independently of most signaling mechanisms
produces a response by lowering the set point of an organism’s metabolism
promotes decreases in metabolic rate rather than increases
|
ensures that conditions in an organism do not vary too much above or below their set points
|
|
In a physiological system operating with positive feedback, _____.
the range of acceptable values for a given parameter will be narrower than if the system were regulated by negative feedback
a stimulus will initiate a response that returns the system to near its initial parameters
a stimulus will prevent a small change from becoming too large
only an effector and control center are necessary to complete the control system
a change in a variable will amplify rather than reverse the change
|
a change in a variable will amplify rather than reverse the change
|
|
Which of the following primarily involves heat transfer by convection?
You sweat profusely as you mow the lawn on a hot summer day.
As you lie on the sand, you can feel the sun’s warm rays on your skin.
The water in the lake is so cold that your legs become numb.
You roll down the car window to allow the cool breeze to blow through.
After sunset, you can feel heat from the warm pavement.
|
You roll down the car window to allow the cool breeze to blow through.
|
|
A countercurrent heat exchanger enables an animal to _____.
reduce the loss of body heat to the environment
increase heat loss by evaporation
absorb heat from the environment
slow metabolism when food is not available
produce more heat when needed
|
reduce the loss of body heat to the environment
|
|
Bats and hummingbirds are examples of _____.
ectotherms that are also poikilotherms
ectotherms that are also homeotherms
endotherms that are also ectotherms
endotherms that are also homeotherms
endotherms that are also poikilotherms
|
endotherms that are also poikilotherms
|
|
Metabolic rate is _____.
the total amount of energy an animal uses in a unit of time
directly proportional to body size
typically higher in an ectothermic animal than in an endothermic one
the amount of heat gained by an animal in a unit of time
determined when the organism is vigorously exercising after consuming a fatty meal
|
the total amount of energy an animal uses in a unit of time
|
|
Choose the list that correctly ranks metabolic rates per gram of body mass, from lowest to highest.
fish, dog, mouse
human, rabbit, snake
gazelle, lion, elephant
hummingbird, dog, mouse
human, cat, mouse, salamander
|
fish, dog, mouse
|
|
When the temperature of the outside air exceeds their internal body temperature, jackrabbits living in hot, arid lands will
increase motor movements to find a sunny area to maximize heat transfer into their bodies.
begin involuntary shivering of their skeletal muscles in order to generate more metabolic heat.
constrict the blood vessels in their large ears to reduce transfer of external heat to the blood in their ears.
increase pigmentation in their ears, darkening them to maximize their capacity to take up heat.
dilate the blood vessels in their large ears to transfer more body heat to the environment.
|
constrict the blood vessels in their large ears to reduce transfer of external heat to the blood in their ears.
|
|
If thermoregulation is considered to be a secondary function of the large ears of jackrabbits, then the primary function of the ears is
to protect offspring from bright sunlight by the positioning of the ears to cast the maximum shadows.
to protect against pathogens by having a thick, waxy surface on the ears.
to optimize nutrient intake through the thin, permeable surfaces on the ears.
to detect predators by using the large size and flexible positioning of the external ears to channel sound waves into the ear canal.
to alter the rate of gas exchange, based on the adjustable radius of the ears’ blood vessels.
|
to detect predators by using the large size and flexible positioning of the external ears to channel sound waves into the ear canal.
|
|
Which choice best describes a reasonable mechanism for animal structures becoming better suited over evolutionary time to specific functions?
Animals that restrict their food intake will become less abundant.
Animals with inventions that curtail reproduction will become more abundant.
Animals with parents that continually improve their offspring’s structures will become more abundant.
Animals with mutations that give rise to effective structures will become more abundant.
Animals that eat the most food become the most abundant.
|
Animals with mutations that give rise to effective structures will become more abundant.
|
|
Penguins, seals, and tuna have body forms that permit rapid swimming, because
the shape is a convergent evolutionary solution to the need to reduce drag while swimming.
this is the only shape that will allow them to maintain a constant body temperature in water.
flying, pregnancy, and gill-breathing all require similar adaptations in form.
all share a common ancestor at some point in the past.
all of their bodies have been compressed since birth by intensive underwater pressures.
|
the shape is a convergent evolutionary solution to the need to reduce drag while swimming.
|
|
The specialized structures of complex animals have evolved because
the development of the specialized structures in an animal is influenced by the animal’s ability to learn.
the most complex animals are the ones with the most ancient evolutionary origin.
they permit adjustments to a wide range of environmental changes.
the simplest animals are those with the most recent appearance among the biota.
the environment imposes identical problems regardless of where the animals are found.
|
they permit adjustments to a wide range of environmental changes.
|
|
All animals, whether large or small, have
each living cell in contact with an aqueous medium.
an external body surface that is dry.
the ability to enter dormancy when resources become scarce.
a basic body plan that resembles a two-layered sac.
a body surface covered with hair to keep them warm.
|
each living cell in contact with an aqueous medium.
|
|
As body size increases in animals,
there is a decrease in the surface-to-volume ratio.
there is greater variability in metabolic rate.
migration to tropical areas becomes necessary for thermoregulation.
it becomes more difficult to conserve body warmth in cold environments.
reproduction becomes limited to terrestrial environments.
|
there is a decrease in the surface-to-volume ratio.
|
|
To increase the effectiveness of exchange surfaces lining the lungs and the intestines, evolutionary pressures have
increased the thickness of the membranes in these linings.
decreased the metabolic rate of the cells in these linings.
increased the exchange surface area with folds and branches.
increased the number of cell layers in these linings.
increased the volume of the cells in these linings.
|
increased the exchange surface area with folds and branches.
|
|
The specialized function shared by the cells that line the lungs and those that line the lumen of the gut is that both types of cells
provide abundant exchange surface.
have a lowered basal metabolic rate due to cooperative exchange between cells.
receive their oxygen directly from inhaled air and ingested foods.
have exceptionally high numbers of cellular organelles in the cytoplasm.
offer greater protection due to increased membrane thickness.
|
provide abundant exchange surface.
|
|
Interstitial fluid is
the route for the exchange of materials between blood and body cells.
identical to the composition of blood.
the fluid inside the gastrovascular cavity of Hydra.
found only in the lumen of the small intestine.
the internal environment inside animal cells.
|
the route for the exchange of materials between blood and body cells.
|
|
Multicellular organisms must keep their cells awash in an "internal pond" because
their cells need to be protected from dissolved nitrogen gas in the blood.
their membranes will crystallize if not in contact with interstitial fluid.
this prevents the loss of water due to osmosis.
an aqueous medium is needed for the cellular exchange of nutrients, gases, and wastes.
terrestrial organisms have not adapted to life in dry environments.
|
an aqueous medium is needed for the cellular exchange of nutrients, gases, and wastes.
|
|
Tissues are composed of cells, and tissues functioning together make up
membranes.
organs.
organelles.
organisms.
organ systems.
|
organs
|
|
An exchange surface in direct contact with the external environment is found in the
heart.
brain.
skeletal muscles.
liver.
lungs.
|
lungs.
|
|
Of the following choices, the epithelium with the shortest diffusion distance is
simple squamous epithelium.
pseudostratified ciliated columnar epithelium.
simple cuboidal epithelium.
simple columnar epithelium.
stratified squamous epithelium.
|
simple squamous epithelium.
|
|
The absorptive epithelia in the gut are considered "polarized" because
thick and thin filaments are present.
the structures on the apical surface are different than those on the basal surface.
they must fire action potentials to absorb most nutrients.
they pump wastes into the lumen while pumping nutrients toward the blood.
the colors seen on the top and bottom of the cells are different.
|
the structures on the apical surface are different than those on the basal surface.
|
|
Most of the exchange surfaces of multicellular animals are lined with
neural tissue.
adipose tissue.
connective tissue.
epithelial tissue.
smooth muscle cells.
|
epithelial tissue.
|
|
An example of a connective tissue is the
cuboidal epithelium.
smooth muscles.
blood.
skin.
nerves.
|
blood.
|
|
Stratified cuboidal epithelium is composed of
a tight layer of square cells attached to a basement membrane.
several layers of boxlike cells.
an irregularly arranged layer of pillarlike cells.
a hierarchical arrangement of flat cells.
a layer of ciliated, mucus-secreting cells.
|
several layers of boxlike cells.
|
|
Coordinating body functions via chemical signals is accomplished by
the immune and lymphatic systems.
the respiratory system.
the endocrine system.
the excretory system.
the integumentary system.
|
the endocrine system.
|
|
Connective tissues typically have
a supporting material such as chondroitin sulfate.
the ability to transmit electrochemical impulses.
the ability to shorten upon stimulation.
relatively few cells and a large amount of extracellular matrix.
many densely packed cells with direct connections between the membranes of adjacent cells.
|
relatively few cells and a large amount of extracellular matrix.
|
|
If you gently twist your earlobe, it does not remain distorted because it contains
loose connective tissue.
adipose tissue.
elastic fibers.
collagenous fibers.
reticular fibers.
|
elastic fibers.
|
|
The nourishment, insulation, and support for neurons is the result of activity by the
adipose tissue.
smooth muscles.
intercalated disks.
endocrine system.
glial cells.
|
glial cells.
|
|
Most types of communication between cells utilize
the movement of the cells.
a direct electrical connection between the cells.
the release of chemical signals by the cell sending the message.
the exchange of cytosol between the cells.
the exchange of DNA between the cells.
|
the release of chemical signals by the cell sending the message.
|
|
The body’s automatic tendency to maintain a constant and optimal internal environment is termed
balanced equilibrium.
estivation.
physiological chance.
homeostasis.
static equilibrium.
|
homeostasis.
|
|
An example of a properly functioning homeostatic control system is seen when
the blood pressure increases in response to an increase in blood volume.
a blood cell shrinks when placed in a solution of salt and water.
the kidneys excrete salt into the urine when dietary salt levels rise.
the core body temperature of a runner rises gradually from 37°C to 45°C.
the level of glucose in the blood is abnormally high whether or not a meal has been eaten.
|
the kidneys excrete salt into the urine when dietary salt levels rise.
|
|
An example of effectors’ roles in homeostatic responses is observable when
an increase in body temperature results from exercise.
an increase in body temperature results from involuntary shivering.
a decrease in body temperature results from shock.
the rising sun causes an increase in body temperature in a stationary animal.
an increase in body temperature results from fever.
|
an increase in body temperature results from involuntary shivering.
|
|
Positive feedback differs from negative feedback in that
the positive feedback’s effector responses are in the same direction as the initiating stimulus rather than opposite to it.
positive feedback systems have control centers that are lacking in negative feedback systems.
the effector’s response increases some parameter (such as body temperature), whereas in negative feedback it can only decrease the parameter.
positive feedback systems have only effectors, whereas negative feedback systems have only receptors.
positive feedback benefits the organism, whereas negative feedback is detrimental.
|
the positive feedback’s effector responses are in the same direction as the initiating stimulus rather than opposite to it.
|
|
In a survivably cold environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm
expends more energy per kg of body mass than does the endotherm.
invests little energy in temperature regulation.
has greater insulation on its body surface.
metabolizes its stored energy more readily than can the endotherm.
maintains a higher basal metabolic rate.
|
invests little energy in temperature regulation.
|
|
Humans can lose, but cannot gain, heat through the process of
evaporation.
convection.
metabolism.
conduction.
radiation.
|
evaporation.
|
|
An example of an ectothermic organism that has few or no behavioral options when it comes to its ability to adjust its body temperature is a
bluefin tuna, a predatory fish.
sea star, a marine invertebrate.
honeybee in a hive.
terrestrial lizard.
hummingbird.
|
sea star, a marine invertebrate.
|
|
The panting responses that are observed in overheated birds and mammals dissipates excess heat by
hibernation.
vasoconstriction.
acclimation.
countercurrent exchange.
evaporation.
|
evaporation.
|
|
An example of an organism that has only behavioral controls over its body temperature is the
penguin.
gray wolf.
house sparrow.
green frog.
bluefin tuna.
|
green frog.
|
|
Most land-dwelling invertebrates and all of the amphibians
become more active when environmental temperatures drop below 15°C.
alter their metabolic rates to maintain a constant body temperature of 37°C.
are endotherms but become thermoconformers only when they are in water.
are ectothermic organisms with variable body temperatures.
have a net loss of heat across a moist body surface, even in direct sun.
|
are ectothermic organisms with variable body temperatures.
|
|
The temperature-regulating center of vertebrate animals is located in the
hypothalamus.
liver.
medulla oblongata.
subcutaneous layer of the skin.
thyroid gland.
|
hypothalamus.
|
|
A female Burmese python incubating her eggs can warm them using
torpor.
nonshivering thermogenesis.
evaporative cooling.
shivering thermogenesis.
acclimatization.
|
shivering thermogenesis.
|
|
The thin horizontal arrows in the figure above show that
the warmer arterial blood transfers heat to the cooler venous blood.
the goose’s legs get progressively warmer as the blood moves away from the abdomen to the feet.
the arterial blood is always cooler in the abdomen, compared to the temperature of the venous blood in the feet of the goose.
the warmer arterial blood can bypass the legs as needed, when the legs are too cold to function well.
the warmer venous blood transfers heat to the cooler arterial blood.
|
the warmer arterial blood transfers heat to the cooler venous blood.
|
|
Examine the figure above. Near a goose’s abdomen, the countercurrent arrangement of the arterial and venous blood vessels causes
the temperature at the abdomen to be less than the temperature at the feet.
the loss of the maximum possible amount of heat to the environment.
the venous blood to be as cold near the abdomen as it is near the feet.
the blood in the feet to be as warm as the blood in the abdomen.
the temperature difference between the contents of the two sets of vessels to be minimized.
|
the temperature difference between the contents of the two sets of vessels to be minimized.
|
|
To prepare flight muscles for use on a cool morning, hawkmoths
decrease their standard metabolic rate.
walk to shaded areas to avoid direct sunlight.
reduce the metabolic rate of the muscles to rest them before flight.
relax the muscles completely until after they launch themselves into the air.
rapidly contract and relax these muscles to generate metabolic warmth.
|
rapidly contract and relax these muscles to generate metabolic warmth.
|
|
The thermoregulatory response of an overheated dog in a very hot environment is impaired if the response causes
body temperature to increase to match the environmental temperature.
a behavioral response that takes the dog to a cooler location.
blood vessels near the skin to vasoconstrict.
evaporative heat loss to increase.
metabolic heat production to decrease.
|
body temperature to increase to match the environmental temperature.
|
|
Seasonal changes in snake activity are due to the fact that the snake
is more active in summer because that is the period for mating.
is less active in winter because the food supply is decreased.
is less active in winter because it does not need to avoid predators.
is more active in summer as a result of being disturbed by other animals.
is more active in summer because it can gain body heat by conduction.
|
is more active in summer because it can gain body heat by conduction.
|
|
Standard metabolic rate (SMR) and basal metabolic rate (BMR) are
used to compare metabolic rate between hibernating and nonhibernating states.
both measured across a wide range of temperatures for a given species.
used differently: SMR is measured during exercise, whereas BMR is measured at rest.
both measured in animals in a resting and fasting state.
both standard measurements of fat metabolism in mammals.
|
both measured in animals in a resting and fasting state.
|
|
Hibernation and estivation during seasons of environmental stress are both examples of
torpor.
acclimatization.
evaporative cooling.
shivering thermogenesis.
nonshivering thermogenesis.
|
torpor.
|
|
Panting by an overheated dog achieves cooling by
shivering thermogenesis.
torpor.
evaporation.
nonshivering thermogenesis.
acclimatization.
|
evaporation.
|
|
A moth preparing for flight on a cold morning warms its flight muscles via
nonshivering thermogenesis.
torpor.
evaporative cooling.
shivering thermogenesis.
acclimatization.
|
shivering thermogenesis.
|
|
Imagine that you are a biologist who is attempting to get an accurate measure of an animal’s basal metabolic rate. The best time to measure the metabolic rate is when the animal
is resting and has not eaten its first meal of the day.
has just completed 30 minutes of vigorous exercise.
has recently eaten a sugar-free meal.
is resting and has just completed its first meal of the day.
has not consumed any water for at least 48 hours.
|
is resting and has not eaten its first meal of the day.
|
|
Tunas, sharks, penguins, and dolphins all have a basic fusiform shape, tapered at both ends. What explains this similarity in shape?
The similarity is due to convergent evolution, because all these animals share similar environmental challenges.
The similarity is due to homology, based on shared ancestry.
All fast-swimming aquatic vertebrates have this shape.
|
The similarity is due to convergent evolution, because all these animals share similar environmental challenges.
|
|
Select the correct statement describing feedback control in animals.
An animal may be a regulator for one environmental variable but a conformer for another.
Ectotherms are regulators with respect to temperature.
Positive feedback loops contribute to homeostasis.
|
An animal may be a regulator for one environmental variable but a conformer for another.
|
|
How do endotherms and ectotherms differ?
Endotherms are warm-blooded and ectotherms are cold-blooded.
Endotherms are regulators and ectotherms are conformers.
Endotherms and ectotherms differ in the means by which they regulate their body temperature.
|
Endotherms and ectotherms differ in the means by which they regulate their body temperature.
|
|
Which statement about endotherms and ectotherms is correct?
Ectotherms are more abundant and diverse than endotherms.
Endothermy is a more successful strategy for thermoregulation than ectothermy.
Ectotherms are more primitive than endotherms.
|
Ectotherms are more abundant and diverse than endotherms.
|
|
Two graphs. One showing the relationship of basal metabolic rate to body size for various mammals. The other showing the relationship of BMR per kilogram of body mass to body size.
Look at the graphs and choose the correct statement describing the relationship between BMR (basal metabolic rate) and body mass of mammals. (Look carefully at the quantity being displayed on the y-axis of each figure.)
Large mammals have lower basal metabolic rates than small mammals.
BMR is roughly proportional to body mass squared.
Small mammals have lower BMR, but use more calories per kilogram than large mammals.
|
Small mammals have lower BMR, but use more calories per kilogram than large mammals.
|
