BIOL EXAM 3B

Which statement about endotherms and ectotherms is correct? A. Ectotherms are more abundant and diverse than endotherms. B. Ectotherms are more primitive than endotherms. C. Endothermy is a more successful strategy for thermoregulation than ectothermy.

A. Ectotherms are more abundant and diverse than endotherms.

Which of the following is a correct statement about an organism and its environment? A. The interstitial fluid is the exchange medium between body cells and the circulatory system in vertebrate animals. B. The gastrovascular cavity provides the nutrient exchange surface in mammals. C. An animal is a closed system that is separate and distinct from its environment. D. Animals isolated from their environments live longer than those exchanging matter with the environment. E. None of the choices is correct.

A. The interstitial fluid is the exchange medium between body cells and the circulatory system in vertebrate animals.

Most types of communication between cells utilize _____. A. chemical or electrical signals B. the movement of the cells C. the exchange of cytosol between the cells D. the exchange of DNA between the cells

A. chemical or electrical signals

Much of the coordination of vertebrate body functions via chemical signals is accomplished by the _____. A. endocrine system B. excretory system C. integumentary system D. respiratory system

A. endocrine system

The panting responses that are observed in overheated birds and mammals dissipate excess heat by _____. A. evaporation B. countercurrent exchange C. vasoconstriction D. acclimation

A. evaporation

All types of muscle tissue have _____. A. interactions between actin and myosin B. cells that lengthen when appropriately stimulated C. striated banding patterns seen under the microscope D. a response that can be consciously controlled

A. interactions between actin and myosin

Compared with a smaller cell, a larger cell of the same shape has A. less surface area per unit of volume. B. less surface area. 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.

A. less surface area per unit of volume.

Homeostasis is the _____. A. maintenance of a relatively constant and optimal internal environment B. cooperation of body parts to form tissues, organs, and systems C. correlation of structure and function D. exchange of materials with the surrounding environment E. idea that all vertebrates are built in a similar way

A. maintenance of a relatively constant and optimal internal environment

Penguins, seals, and tuna have body forms that permit rapid swimming, because _____. A. the shape is a convergent evolutionary solution, which reduces drag while swimming B. all of their bodies have been compressed since birth by intensive underwater pressures C. this is the only shape that will allow them to maintain a constant body temperature in water D. all share a recent common ancestor

A. the shape is a convergent evolutionary solution, which reduces drag while swimming

How do endotherms and ectotherms differ? A. Endotherms are regulators and ectotherms are conformers. B. Endotherms and ectotherms differ in the means by which they regulate their body temperature. C. Endotherms are warm-blooded and ectotherms are cold-blooded.

B. Endotherms and ectotherms differ in the means by which they regulate their body temperature.

Which of the following is a true statement about body size and physiology? A. The rate at which an animal uses nutrients and produces waste products is independent of its volume. B. Small and large animals face different physiological challenges because an animal's body mass increases cubically while its surface area increases as a squared function. C. The wastes produced by an animal double as its volume doubles and triple as its surface area triples. D. The amount of food and oxygen an animal requires and the amount of heat and waste it produces are inversely proportional to its mass.

B. Small and large animals face different physiological challenges because an animal's body mass increases cubically while its surface area increases as a squared function.

An elephant and a mouse are running in full sunlight, and both overheat by the same amount above their normal body temperatures. When they move into the shade and rest, which animal will cool down faster? A. The elephant will because it has the lower surface-area-to-volume ratio. B. The mouse will because it has the higher surface-area-to-volume ratio. C. The elephant will because it has the higher surface-area-to-volume ratio. D. They will cool at the same rate because they overheated by the same amount.

B. The mouse will because it has the higher surface-area-to-volume ratio.

Which of the following is an example of negative feedback? A. When a baby is nursing, suckling leads to the production of more milk and a subsequent increase in the secretion of prolactin (a hormone that stimulates lactation). B. When the level of glucose in the blood increases, the pancreas produces and releases the hormone insulin. Insulin acts to decrease blood glucose. As blood glucose decreases, the rate of production and release of insulin decreases as blood glucose decreases. C. After a blood vessel is damaged, signals are released by the damaged tissues that activate platelets in the blood. These activated platelets release chemicals that activate more platelets. D. During birthing contractions, oxytocin (a hormone) is released and acts to stimulate further contractions.

B. When the level of glucose in the blood increases, the pancreas produces and releases the hormone insulin. Insulin acts to decrease blood glucose. As blood glucose decreases, the rate of production and release of insulin decreases as blood glucose decreases.

Which of the following primarily involves heat transfer by convection? A. After sunset, you can feel heat from the warm pavement. B. You roll down the car window to allow the cool breeze to blow through. C. The water in the lake is so cold that your legs become numb. D. You sweat profusely as you mow the lawn on a hot summer day. E. As you lie on the sand, you can feel the sun's warm rays on your skin.

B. You roll down the car window to allow the cool breeze to blow through.

Interstitial fluid is _____. A. found only in the lumen of the small intestine B. a common site of exchange between blood and body cells C. the internal environment inside animal cells D. identical to the composition of blood

B. a common site of exchange between blood and body cells

Most land-dwelling invertebrates and all of the amphibians _____. A. alter their metabolic rates to maintain a constant body temperature of 37°C B. are ectothermic organisms with variable body temperatures C. are endotherms but become thermoconformers when they are in water D. become more active when environmental temperatures drop below 15°C

B. are ectothermic organisms with variable body temperatures

You discover a new species of bacteria that grows in aquatic environments with high salt levels. While studying these bacteria, you note that their internal environment is similar to the salt concentrations in their surroundings. You also discover that the internal salt concentrations of the bacteria change as the salt concentration in their environment changes. The new species can tolerate small changes in this way, but dies from large changes because it has no mechanism for altering its own internal salt levels. What type of homeostatic mechanism is this species using to regulate its internal salt levels? A. regulation B. conformation C. assimilation D. integration

B. conformation

The body tissue that consists largely of material located outside of cells is _____. A. skeletal muscle B. connective tissue C. epithelial tissue D. nervous tissue

B. connective tissue

You are looking through a microscope at a slide of animal tissue and see a single layer of flat, closely packed cells that cover a surface. This specific tissue is most likely _____. A. a tendon B. epithelial C. a neuron D. adipose

B. epithelial

Most of the exchange surfaces of multicellular animals are lined with _____. A. smooth muscle cells B. epithelial tissue C. connective tissue D. neural tissue

B. epithelial tissue

Sweating allows a person to lose heat through the process of _____. A. conduction B. evaporation C. convection D. radiation

B. evaporation

The body's automatic tendency to maintain a constant and optimal internal environment is termed _____. A. static equilibrium B. homeostasis C. balanced equilibrium D. physiological chance

B. homeostasis

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

B. hypothalamus

A countercurrent heat exchanger enables an animal to _____. A. slow metabolism when food is not available B. reduce the loss of body heat to the environment C. absorb heat from the environment D. produce more heat when needed E. increase heat loss by evaporation

B. reduce the loss of body heat to the environment

Of the following choices, the epithelium with the shortest diffusion distance is _____. A. pseudostratified ciliated columnar epithelium B. simple squamous epithelium C. stratified squamous epithelium D. simple columnar epithelium

B. simple squamous epithelium

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

B. simple squamous epithelium

Food moves along the digestive tract as the result of contractions by _____. A. cardiac muscle B. smooth muscle C. skeletal muscle D. striated muscle

B. smooth muscle

Positive feedback differs from negative feedback in that _____. A. the effector's response increases some parameter (such as body temperature), whereas in negative feedback it can only decrease the parameter B. the positive feedback's effector responses are in the same direction as the initiating stimulus rather than opposite of it C. positive feedback systems have only effectors, whereas negative feedback systems have only receptors D. positive feedback benefits the organism, whereas negative feedback is detrimental

B. the positive feedback's effector responses are in the same direction as the initiating stimulus rather than opposite of it

Select the correct statement describing feedback control in animals. A. Positive feedback loops contribute to homeostasis. B. Ectotherms are regulators with respect to temperature. C. An animal may be a regulator for one environmental variable but a conformer for another.

C. An animal may be a regulator for one environmental variable but a conformer for another.

Some animals have no gills when young, but then develop gills that grow larger as the animal grows larger. What is the reason for this increase in gill size? A. Relative to their surface area, the young have more body volume in which they can store oxygen for long periods of time. B. The young have a higher basal metabolic rate. C. Relative to their volume, the young have more surface area across which they can transport all the oxygen they need. D. The young of these animals are much more active than the adult, which leads to a higher BMR (basal metabolic rate) and, therefore, a higher need for oxygen.

C. Relative to their volume, the young have more surface area across which they can transport all the oxygen they need.

Tunas, sharks, penguins, and dolphins all have a basic fusiform shape, tapered at both ends. What explains this similarity in shape? A. All fast-swimming aquatic vertebrates have this shape. B. The similarity is due to homology, based on shared ancestry. C. The similarity is due to convergent evolution, because all these animals share similar environmental challenges.

C. The similarity is due to convergent evolution, because all these animals share similar environmental challenges.

In a physiological system operating with positive feedback, _____. A. the range of acceptable values for a given parameter will be narrower than if the system were regulated by negative feedback B. a stimulus will prevent a small change from becoming too large C. a change in a variable will amplify rather than reverse the change D. a stimulus will initiate a response that returns the system to near its initial parameters E. only an effector and control center are necessary to complete the control system

C. a change in a variable will amplify rather than reverse the change

If you were to view a sample of animal tissue under a light microscope and notice an extensive extracellular matrix surrounding a tissue, which tissue type would you most suspect? A. striated muscle B. epithelial C. connective D. nervous

C. connective

If you gently bend your ear, and then let go, the shape of your ear will return because the cartilage of your ear contains_____. A. adipose tissue B. collagenous fibers C. elastic fibers D. reticular fibers

C. elastic fibers

There are advantages and disadvantages to adaptations. Animals that are endothermic are likely to be at the greatest disadvantage in _____. A. very hot environments B. environments with a constant food source C. environments with variable and limited food sources D. very cold environments

C. environments with variable and limited food sources

In a cool environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm _____. A. expends more energy per kilogram of body mass than does the endotherm B. has greater insulation on its body surface C. invests little energy in temperature regulation D. maintains a higher basal metabolic rate

C. invests little energy in temperature regulation

Blood is best classified as connective tissue because _____. A. it contains more than one type of cell B. its cells can move from place to place C. its cells are separated from each other by an extracellular matrix D. it is found within all the organs of the body

C. its cells are separated from each other by an extracellular matrix

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

C. less surface area per unit of volume

The four major categories of tissues are _____. A. blood, nervous, connective, and muscle B. muscle, epithelial, bone, and cartilage C. nervous, epithelial, connective, and muscle D. simple squamous, simple cuboidal, simple columnar, and stratified squamous E. bone, muscle, blood, and adipose

C. nervous, epithelial, connective, and muscle

Cardiac muscle cells are both _____. A. striated and under voluntary control B. smooth and under voluntary control C. striated and interconnected by intercalated disks D. smooth and under involuntary control

C. striated and interconnected by intercalated disks

You have a cube of modeling clay in your hands. Which of the following changes to the shape of this cube of clay will decrease its surface area relative to its volume? A. Pinch the edges of the cube into small folds. B. Stretch the cube into a long, shoebox shape. C. Flatten the cube into a pancake shape. D. Round the clay up into a sphere.

D. Round the clay up into a sphere.

As the size of some animals has evolved to greater sizes, the effectiveness of their adaptations that promote exchanges with the environment have also increased. For example, in many larger organisms, evolution has favored lungs and a digestive tract with _____. A. increased thickness B. decreased blood supply C. larger cells D. more branching or folds

D. more branching or folds

All animals, whether large or small, have _____. A. a basic body plan that resembles a two-layered sac B. a body surface covered with hair to keep them warm C. an external body surface that is dry D. most of their cells in contact with an aqueous medium

D. most of their cells in contact with an aqueous medium

When the body's blood glucose level rises, the pancreas secretes insulin and, as a result, the blood glucose level declines. When the blood glucose level is low, the pancreas secretes glucagon and, as a result, the blood glucose level rises. Such regulation of the blood glucose level is the result of _____. A. positive feedback B. protein-protein interactions C. catalytic feedback D. negative feedback

D. negative feedback

The metabolic breakdown of specialized brown fat depots in certain animals is substantially increased during _____. A. torpor B. acclimatization C. shivering thermogenesis D. nonshivering thermogenesis

D. nonshivering thermogenesis

Once labor begins in childbirth, contractions increase in intensity and frequency, causing more contractions to occur until delivery. The increasing labor contractions of childbirth are an example of which type of regulation? A. negative feedback B. enzymatic catalysis C. feedback inhibition D. positive feedback

D. positive feedback

Connective tissues typically have _____. A. little space between the membranes of adjacent cells B. the ability to transmit electrochemical impulses C. the ability to shorten upon stimulation D. relatively few cells and a large amount of extracellular matrix

D. relatively few cells and a large amount of extracellular matrix

The type of muscle tissue surrounding the intestines and blood vessels is _____. A. skeletal muscle B. cardiac muscle C. intercalated cells D. smooth muscle

D. smooth muscle

The body tissue that consists largely of material located outside of cells is A. nervous tissue. B. smooth muscle. C. epithelial tissue. D. skeletal muscle. E. connective tissue.

E. connective tissue.

Negative feedback is a method of homeostatic control that _____. A. operates independently of most signaling mechanisms B. produces a response by lowering the set point of an organism's metabolism C. increases the speed and rapidity of negative responses to environmental stimuli D. promotes decreases in metabolic rate rather than increases E. ensures that conditions in an organism do not vary too much above or below their set points

E. ensures that conditions in an organism do not vary too much above or below their set points