7) Evolutionary adaptations that help some animals directly exchange matter between the cells of their body and the environment include ________.
A) a gastrovascular cavity, a two-layered body, and a torpedo-like body shape
B) an external respiratory surface, a small body size, and a two-cell-layered body

C) a large body volume, a long, tubular body, and a set of wings
D) an unbranched internal surface, a small body size, and thick covering

B

8) 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) most of their cells in contact with an aqueous medium

D

24) Which of the following is a true statement about body size and physiology?
A) 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) The rate at which an animal uses nutrients and produces waste products is independent of its volume.
C) 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.
D) The wastes produced by an animal double as its volume doubles and triple as its surface area triples.

C

25) 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 higher surface-area-to-volume ratio.

B) The elephant will because it has the lower surface-area-to-volume ratio.
C) The mouse 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

C

26) 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) Flatten the cube into a pancake shape.

C) Round the clay up into a sphere.
D) Stretch the cube into a long, shoebox shape.

C

38) 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) maintains a higher basal metabolic rate
B) expends more energy per kilogram of body mass than does the endotherm

C) invests little energy in temperature regulation

D) has greater insulation on its body surface

C

39) Elephants can often be observed cooling off by spraying water over their bodies with their trunks. What type of heat exchange is occurring?
A) conduction
B) convection

C) radiation
D) evaporation

D

40) 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 ________.
A) sea star living deep in the ocean
B) bass living in a farm pond

C) hummingbird flying through a prairie

D) honeybee in a hive on a rural farm

A

42) Most land-dwelling invertebrates and all of the amphibians ________.
A) are ectothermic organisms with variable body temperatures
B) alter their metabolic rates to maintain a constant body temperature of 37°C

C) are endotherms but become thermo-conformers when they are in water
D) become more active when environmental temperatures drop below 15°C

A

43) The temperature-regulating center of vertebrate animals is located in the ________.

A) thyroid gland
B) hypothalamus
C) subcutaneous layer of the skin

D) liver

B

45) The use of brown fat to generate metabolic heat is mostly limited to small mammals. What is the basis of this adaptation?
A) Small mammals cannot grow enough fur to insulate their bodies.
B) Because of their large surface area to volume ratio, heat loss across the body surface is higher in small animals.

C) Small mammals do not have enough muscle to generate heat by shivering.
D) Large mammals have lost their brown fat through the course of their evolution.

B

60) Hummingbirds are small birds that require a regular food supply. When hummingbirds are faced with a situation that decreases their food supply, such as a storm, which of the following adaptations would be most useful for the bird to survive such an unpredictable and short-term absence of food resources?

A) shivering
B) torpor
C) hibernation
D) burrowing into soil

B