Deck 11: Food, Energy, and Temperature at Work: The Lives of Mammals in Frigid Places

Question 1

The biggest threat to a newborn reindeer's life upon birth is

A) its lack of camouflage.
B) the immediate risk of predation.
C) the significant temperature drop.
D) its lack of being able to move.

Answer 1

C

Question 2

In winter, reindeer have low energy costs because they

A) increase their heart rate.
B) change their behavior by constantly moving to warm up.
C) maintain different temperatures in different body parts.
D) hide in caves where the temperature is warmer.

Answer 2

C

Question 3

According to the experiment done by Nilssen et al. (1984), the resting metabolic rate in adult reindeer during winter

A) increases dramatically as the air temperature changes from -40°C to -20°C.
B) decreases significantly as the air temperature changes from 20°C to 40°C.
C) remains about the same as the air temperature changes from 0°C to 10°C.
D) decreases drastically as the air temperature changes from 0°C to 10°C.

Answer 3

C

Question 4

Oleic acid is _______ and contains _______ double bond(s).

A) monounsaturated; 1
B) monounsaturated; 2
C) polyunsaturated; 1
D) polyunsaturated; 2

Question 5

Fatty acids isolated from the distal limb of a reindeer would consist of

A) unsaturated fatty acids only.
B) some saturated fatty acids and some unsaturated fatty acids.
C) fatty acids that aggregate to form triglycerides.
D) more unsaturated than saturated fatty acids.

Question 6

Which statement regarding microbes in reindeer rumen is false?

A) Microbes that digest fibers are less prevalent in summer communities than winter communities.
B) Microbes that digest cellulose are less prevalent in winter communities than summer communities.
C) Microbes that digest proteins are more prevalent in summer communities than winter communities.
D) Microbes that digest starch are more prevalent in summer communities than winter communities.

Question 7

In response to seasonal diets, the microbial community in reindeer will preferentially breakdown _______ in the winter.

A) chitin
B) fiber
C) protein
D) starch

Question 8

Refer to the figure shown.
What is this figure showing?

A) Maximum metabolic rate at various temperatures in summer-acclimatized and winter-acclimatized reindeer
B) Resting metabolic rate at various temperatures in summer-acclimatized and winter-acclimatized reindeer
C) Maximum metabolic rate at various temperatures in a northern species and southern species of reindeer
D) Resting metabolic rate at various temperatures in a northern species and southern species of reindeer

Question 9

Refer to the figure shown.
According to the figure, which animal is saving the most energy?

A) Summer-acclimatized reindeer at 10°C
B) Summer-acclimatized reindeer at -30°C
C) Winter-acclimatized reindeer at 10°C
D) Winter-acclimatized reindeer at -30°C

Question 10

Refer to the figure shown.
If animals in both groups of animals were exposed to progressively higher air temperatures than shown, and data collection from the experiment continued, what results would you expect to see?

A) Both metabolic rates would remain flat.
B) Both metabolic rates would decrease, however, the summer-acclimatized reindeer would decrease first.
C) Both metabolic rates would increase, however, the winter-acclimatized reindeer would increase first.
D) Only the summer-acclimatized metabolic rates would decrease.

Question 11

Which animal has the highest mass-specific metabolic rate?

A) Summer-acclimatized reindeer at 10°C
B) Summer-acclimatized reindeer at -30°C
C) Winter-acclimatized reindeer at 10°C
D) Winter-acclimatized reindeer at -30°C

Question 12

Reindeer have low energy costs in cold environments because of their

A) skin.
B) pelage.
C) hypodermis.
D) antlers.

Question 13

In winter, reindeer _______ is _______ thick.

A) fur; 3-4 cm
B) fur; 1-2 cm
C) skin; 3-4 cm
D) skin; 1-2 cm

Question 14

As the ambient temperature drops below zero, a newborn reindeer's resting metabolic rate

A) increases.
B) decreases.
C) stays the same.
D) decreases first and then levels off.

Question 15

If a newborn reindeer's maximum rate of metabolic heat production is 10 watts/kg, its resting metabolic rate is _______ watts/kg.

A) 20
B) 10
C) 5
D) 15

Question 16

Which protein is found in brown fat?

A) UCP1
B) UCP2
C) UCP1 and UCP2
D) UCP1 and UCP3

Question 17

Which hormone was used to test for brown-fat function in newborn reindeer?

A) Thyroxine
B) Epinephrine
C) Cortisol
D) Testosterone

Question 18

Which marker is used to test for the presence of brown fat?

A) UCP1
B) Lactate dehydrogenase
C) UCP2
D) Hexokinase

Question 19

In newborn humans, brown fat concentration is

A) high and remains high throughout growth.
B) low and remains low throughout growth.
C) high and declines as growth occurs.
D) low and increases as growth occurs.

Question 20

If you were to do an immunocytochemistry experiment on a newborn reindeer, a one-month-old reindeer, and a two-month-old reindeer to test for the presence of brown fat, your results would show a _______ amount of brown fat on the _______ compared to the _______-month old.

A) higher; newborn; one
B) lower; newborn; one
C) lower; newborn; two
D) higher; one-month-old; two

Question 21

The elevated rate of oxygen consumption response to norepinephrine in newborn reindeer has declined by _______ of age.

A) one week
B) one month
C) two months
D) one year

Question 22

The major role of brown fat is to

A) warm the body by acting as insulation.
B) provide an energy source for muscle movement by storing lots of triglycerides.
C) warm the body by nonshivering mechanisms.
D) provide a source of fat for phospholipid synthesis.

Question 23

If an adult animal had a lot of brown fat,

A) its metabolic rate would be higher at rest compared to an animal of the same size that does not have a lot of brown fat.
B) its metabolic rate would be lower during exercise compared to an animal of the same size that does not have a lot of brown fat.
C) it would facilitate the storage of high-energy triglycerides.
D) the metabolism of its brown fat cells would increase during exercise due to the release of cortisol.

Question 24

Which would have more brown fat, a lamb born in Palm Desert or one born in Alaska?

A) The lamb born in Alaska
B) The lamb born in Palm Desert
C) Both lambs will have an equal amount of brown fat
D) Neither; brown fat is not produced in sheep

Question 25

Which newborn animal does not have brown fat?

A) Reindeer
B) Mice
C) Lamb
D) Piglet

Question 26

Studies on domestic pigs have shown that the UCP1 gene is

A) duplicated.
B) mutated during the birthing process.
C) mutated by a deletion of 2 exons.
D) mutated by a deletion of 2 introns.

Question 27

How do newborn piglets stay warm?

A) Very thick fur
B) Non-shivering thermogenesis
C) Shivering thermogenesis
D) Very thick layer of blubber

Question 28

Refer to the figure shown.
What does the figure show?

A) Changes in fur thickness as a function of temperature in four different species
B) Changes in metabolic rate as a function of temperature in different seasons
C) Changes in nonshivering thermogenesis as a function of temperature in different aged animals
D) Changes in metabolic rate as a function of temperature in different aged animals

Question 29

Refer to the figure shown.
Which line most closely approximates an adult animal in the summer season?

A) I
B) II
C) III
D) IV

Question 30

Lambs born to shorn mothers _______ at birth compared to lambs born to unshorn mothers.

A) shiver more
B) engage in exercise more
C) have more brown fat
D) have less brown fat

Question 31

If near-term sheep fetuses with normal blood circulation are cooled inside the uteruses of their mothers,

A) brown fat is upregulated.
B) the fetus shivers.
C) fetal metabolic rate increases.
D) nothing happens.

Question 32

One of the negative consequences to reindeer of rain falling in Arctic areas instead of snow is

A) rain is warmer than snow.
B) rain is more difficult to migrate through than snow.
C) rain freezes on the ground and ices in food plants.
D) rain freezes on the ground and compromises migration.

Question 33

Which animal will have the greatest amount of brown fat, relative to its body, at birth?

A) Lamb
B) Piglet
C) Mouse
D) Rat

Question 34

Which will favor nonshivering thermoregulation at birth, a reindeer or a mouse?

A) The reindeer, because it is a larger mammal.
B) Both mice and reindeer use nonshivering thermogenesis at birth.
C) The mouse, because it is a small mammal.
D) The mouse, because it has to avoid predators.

Question 35

Which mammal would be most likely to maintain some brown fat as an adult?

A) Mouse
B) Beaver
C) Dog
D) Reindeer

Question 36

Which statement about white-footed mice newborns is false?

A) They are born in a highly protective habitat.
B) They can fully thermoregulate in isolation.
C) They do not have any fur covering their bodies.
D) They can keep warm by shivering in secluded underground burrows.

Question 37

Which of the following is an advantage for small mammals, such as lemmings, in the winter?

A) They can escape the cold by huddling together.
B) They can thermoregulate to lower their core temperature when ambient temperatures are -30°C.
C) They can escape the cold by living under the snow.
D) They can keep warm because they grow a very thick pelage.

Question 38

The single greatest option large-bodied mammals have to beat the cold environment is

A) migration.
B) daily torpor.
C) hibernation.
D) growing fur.

Question 39

Which animal is most likely to have the advantage of migration to a warmer region as winter approaches?

A) Adult white footed mouse
B) Lemming
C) Alpine marmot
D) Bighorn sheep

Question 40

Based on the relationship of metabolic rate and body weight, an animal that weighs _______ kg as an adult is most likely to hibernate.

A) 4
B) 9
C) 10
D) 20

Question 41

Which animal has the lowest weight-specific metabolic rate?

A) Nonhibernating mouse
B) Small reindeer
C) Bear
D) Elephant

Question 42

An animal that weighs _______ will have the lowest weight-specific metabolic rate.

A) 100 g
B) 1000 g
C) 10 kg
D) 100 kg

Question 43

Physiologists have always pondered the relationship of body size to the evolution of hibernation. Based on evolutionary theory, an animal of that weighs _______ kg will have the least energy savings in hibernation.

A) 400
B) 300
C) 200
D) 100

Question 44

Which animal will have the highest weight-specific metabolic rate during hibernation?

A) Mouse
B) Marmot
C) Bear
D) All animals listed will have the same mass-specific metabolic rate during hibernation.

Question 45

Which hibernating animal will have the highest weight-specific metabolic rate in the summer?

A) Mouse
B) Marmot
C) Bear
D) All animals listed will have the same mass-specific metabolic rate in the summer.

Question 46

Which animal does not hibernate?

A) Arctic ground squirrel
B) Reindeer
C) Alpine marmot
D) Hoary bat

Question 47

Permafrost is

A) soil that thaws in the summer.
B) soil that never freezes.
C) soil that never melts throughout the year.
D) frost that never melts, (e.g., icebergs).

Question 48

Ground squirrels that live in the Arctic Circle cannot burrow deeper than _______ m.

A) 0.1
B) 0.5
C) 0.8
D) 1

Question 49

During winter in the Arctic Circle, the temperature inside a ground squirrel hibernacula could reach as low as

A) -25°C.
B) -20°C.
C) -10°C.
D) 10°C.

Question 50

The fat stored in animals prior to hibernation is in the form of

A) fatty acids.
B) glycerol.
C) triacylglycerols.
D) phospholipids.

Question 51

Which of the following is most likely the cue for animals to begin to store nutrients in preparation for hibernation?

A) Changes in Earth's magnetic field
B) Decrease in length of daylight in the fall
C) Change in temperature in the spring
D) Change in temperature in the fall

Question 52

Researchers have shown that animals that consume a diet rich in _______ can tolerate the lowest body temperature without being aroused from hibernation.

A) carbohydrates
B) protein
C) saturated fats
D) unsaturated fats

Question 53

When experimental animals are fed different diets and their subsequent hibernation times are measured, the animals that hibernate the most effectively are animals that were fed a _______ diet.

A) starchy
B) polyunsaturated fatty acid
C) mixed 75% saturated and 25% unsaturated fat
D) protein

Question 54

When experimental animals are fed different diets and their body temperature is monitored during subsequent hibernation, the animals that tolerate the lowest body temperature without arousal are the animals that were fed a

A) carbohydrate-rich diet.
B) polyunsaturated fatty acids diet.
C) mixed diet of 65% saturated and 35% unsaturated fat.
D) protein diet.

Question 55

When experimental animals are fed different diets and the length of each continuous hibernation bout at an ambient temperature of 5° C is measured, animals that have the shortest continuous hibernation bouts are the animals that have been fed a

A) carbohydrate-rich diet.
B) polyunsaturated fatty acids diet.
C) saturated fat diet.
D) protein-rich diet.

Question 56

Which type of fat is important for calcium pump function in heart cells at low temperatures?

A) Saturated fatty acids
B) Triglycerides
C) Omega-3 fatty acids
D) Omega-6 fatty acids

Question 57

In ground squirrels, testosterone levels _______ during hibernation.

A) increase
B) decrease
C) stay the same
D) initially increase and then decrease

Question 58

Which statement about small hibernating mammals is true?

A) Their chances for survival increase during hibernation.
B) Their chances for survival decrease with hibernation.
C) Their chances of encountering a predator increase with hibernation.
D) Testosterone plasma levels increase during hibernation.

Question 59

In ground squirrels, males emerge before females because

A) males have more body mass and therefore can arouse sooner.
B) males have less brown fat and therefore cannot hibernate as long as females can.
C) the higher testosterone levels in males rouses them.
D) the testicles shrink during hibernation, so males emerge first to prepare to be successful mates.

Question 60

Refer to the figure shown.
In the figure, what do the arrows represent?

A) Energy savings per gram per hour during hibernation
B) The aerobic scope per gram per hour in relation to body mass
C) The winter season metabolic effect per gram per hour
D) The mass effect on cost of metabolism with winter fur insulation

Question 61

Refer to the figure shown.
Which statement is not supported by data shown in the figure?

A) Larger animals save less energy during hibernation.
B) Smaller animals have higher nonhibernating metabolic rates.
C) There is no mass effect on metabolic rate in hibernating animals.
D) The larger the animal, the less likely they are to hibernate.

Question 62

Refer to the figure shown.
What is the most accurate title for this figure?

A) Annual cycle of energy use in alpine marmots
B) Annual metabolic rate cycling in ground squirrels
C) Hibernation frequency in alpine marmots
D) Hibernation effects on metabolic rate in ground squirrels

Question 63

Refer to the figure shown.
What best represents the actual cost savings of hibernation?

A) Line I
B) The difference between line I and line II
C) Line II
D) The difference between line II and line III

Question 64

Refer to the figure shown.
What is indicated by the arrow in the figure?

A) End of hibernation
B) Birth
C) Beginning of hibernation
D) Beginning of mating season

Question 65

Refer to the figure shown.
Which conclusion is best supported by the data in the figure?

A) As temperature increases, testicle size and testosterone level increase.
B) Following birth, testicle size and testosterone level increase.
C) Following hibernation, both testosterone levels and testicle size increase.
D) Longer summer days increase testosterone levels and testicle size.

Question 66

An early hypothesis for arousal during hibernation was that animals

A) must wake up to metabolize glucose in their brains.
B) produce nitrogenous wastes and therefore must wake up to void.
C) must wake up because they need to move their muscles regularly.
D) must wake up and move because they need to circulate their blood.

Question 67

Explain the differences between brown fat and white fat.

Question 68

Describe the immunocytochemistry assay that was devised to test for brown fat in newborn reindeer.

Question 69

It has been shown that fetuses inside the uterus do not rely on brown fat and only begin to rely on it after birth. Describe an experiment to test this conclusion.

Question 70

Explain how body size relates to weight-specific metabolic rate in hibernating and nonhibernating animals.

Question 71

Explain how technological advances have helped researchers record data pertaining to hibernation and other physiological mechanisms.

Question 72

Explain how animals prepare for hibernation. Include the cues that trigger preparation, the type of nutrients stored, and the specific location of storage molecules.

Question 73

Explain social hibernation using a specific animal example.

Question 74

Explain the significance of social hibernation.

Question 75

Explain how certain animals undergo synchrony in their hibernation.

Question 76

Which hypotheses for arousal during hibernation are currently popular?