Deck 4: Coping With Environmental Variation:

Question 1

Among vertebrates, _______ can survive a long winter in a semi-frozen state.

A) all species of amphibians and turtles
B) all species of frogs
C) a few species of frogs, salamanders, and turtles
D) one species of frog

Answer 1

C

Question 2

Refer to the figure.


- The figure shows the distribution of aspen in North America and the factors that limit it. What is the most common factor limiting aspen's distribution along the western edge of its range in Canada?

A) Failure to survive drought
B) Failure of fruits to ripen
C) Failure of flowers to survive frost
D) There are no limiting factors along the western edge of the range.

Answer 2

Failure to survive drought

Question 3

Refer to the figure.


-The figure shows the distribution of aspen in North America and the factors that limit it. What is the most common factor limiting aspen's distribution near Lake Ontario?

A) Failure to survive drought
B) Failure of fruits to ripen
C) Failure of flowers to survive frost
D) There are no limiting factors on aspen near Lake Ontario.

Answer 3

There are no limiting factors on aspen near Lake Ontario.

Question 4

Refer to the figure.


-The figure shows the distribution of aspen in North America and the factors that limit it. If aspen evolved an adaptation that made it more drought-tolerant, the expansion of its range would most likely occur

A) in north central Canada.
B) in northwestern Canada and Alaska.
C) across the Great Plains of the United States.
D) in southeastern United States.

Question 5

A tourist travels to the Himalayas. At first, she has difficulty hiking due to shortness of breath, but after a week, her performance has improved. This is most likely an example of _______ to lower partial pressure of oxygen. The lower oxygen condition is also known as _______.

A) adaptation; hyperoxia
B) acclimatization; hypoxia
C) acclimatization; hyperoxia
D) adaptation; hypothermia

Question 6

Which statement about adaptation is true?

A) Genetic adaptations evolve within individuals during an individual's lifetime.
B) "Adaptation" is another word for "acclimatization."
C) Genetic variation within a population is a requirement for the evolution of adaptations.
D) Adaptations to a particular environmental problem is always the same for every population that encounters it.

Question 7

Which statement about ecotypes is true?

A) Ecotypes are populations with adaptations to unique environments.
B) Ecotypes can never become separate species.
C) An ecotype is always able to acclimate to severe cold weather.
D) Ecotypes are a response to abiotic factors only.

Question 8

Which statement about human adaption to hypoxia is true?

A) It requires increases in red blood cell concentrations.
B) Its physiological characteristics vary among different human populations.
C) It involves the development of a larger-than-average lung capacity.
D) It is characterized by higher breathing and blood flow rates.

Question 9

The wooly plant of the Himalayas has adapted to the low temperatures of the alpine zone by growing dense pubescence that provides thermal insulation. What tradeoff occurs because of this adaptation?

A) Reduced radiation at the leaf surface and lower photosynthetic rates
B) Increased radiative warming because of increased reflection from the white hairs
C) Increased water loss because of a thicker boundary layer around leaf
D) Increased daily thermal amplitude because of thicker boundary layer

Question 10

The extreme lower limit for organismal function is reached when body temperature reaches about _______, the temperature at which _______.

A) 0°C; water in cells freezes
B) 0°C; ATP production stops
C) 3°C; enzymes become denatured
D) -3°C; water in cells freezes

Question 11

Which statement best explains why tropical plants may lose function at temperatures as high as 10°C, while alpine plants can function at temperatures close to freezing?

A) The enzymes of tropical plants become denatured at 10°C, whereas the enzymes of alpine plants do not.
B) The membranes of alpine plants have a higher proportion of unsaturated lipids, making them less sensitive to lower temperatures.
C) The metabolic coordination of alpine plants makes them able to withstand lower temperatures.
D) The alpine plants can function even when their membranes have solidified, whereas the tropical plants cannot.

Question 12

Which environment typically experiences the most extreme seasonal variation?

A) Boreal forests
B) Tropical forests
C) Open oceans
D) Tide pools

Question 13

On a warm day, a dog pants and some of the water on its tongue evaporates. This evaporation has a _______ effect that is caused by _______.

A) warming; conduction
B) warming; latent heat transfer
C) cooling; conduction
D) cooling; latent heat transfer

Question 14

If the temperature of a plant is 18°C and the ambient temperature is 14°C, which process will result in a net input of heat from the air to the plant?

A) Conduction
B) Convection
C) Evaporation
D) None of the above

Question 15

Suppose a plant is receiving 150 units of heat per minute due to solar radiation, and 45 units of heat per minute due to infrared radiation. Sixty units per minute of solar radiation are reflected back by the leaves, and the plant emits 30 units of infrared radiation. It also loses 50 units of heat per minute through evapotranspiration. The temperature of the plant is not changing. Based on this information, we can conclude that the combination of conduction and convection is resulting in a net _______of heat by the plant, and that its temperature is currently _______ than the ambient temperature.

A) gain; warmer
B) gain; colder
C) loss; warmer
D) loss; colder

Question 16

A mouse is sitting in the sun. Solar radiation provides a net intake of energy of 30 milliwatts per minute, and infrared radiation provides an additional net input of 8 milliwatts per minute. Conductive and convective outputs are a combined 55 milliwatts per minute. There is no detectable change in heat from evaporation. Assuming that the mouse is maintaining a constant temperature, how much heat must it be generating per minute?

A) 17 milliwatts
B) 25 milliwatts
C) 33 milliwatts
D) 38 milliwatts

Question 17

Refer to the figure.
The figure shows the relationship between the outside temperature and the temperature of three animals. Based on the figure, the body temperature of animal B is approximately _______°C when the outside temperature is 20°C and approximately _______°C when the outside temperature is 35°C.

A) 22; 32
B) 18; 34
C) 22; 36
D) 40; 41

Question 18

In the canopies of tropical forests, plants are able to survive despite the high temperatures and high levels of solar radiation due to the process of

A) reverse evaporation.
B) infrared heat transfer.
C) conductive heat transfer.
D) transpiration.

Question 19

The opening and closing of stomates is controlled by _______. Stomate openings primarily affect the process of _______.

A) guard cells; conduction
B) guard cells; transpiration
C) stomatocytes: conduction
D) stomatocytes; transpiration

Question 20

In which environment is transpiration likely to make the greatest contributor to the cooling of a leaf?

A) A tropical rainforest at noon on a sunny day
B) A hot desert at noon on a cloudy day during a summer drought
C) A boreal forest at noon on the coldest day during the winter
D) A tundra grassland at noon during the winter

Question 21

Which statement about the condition known as pubescence is false?

A) Light-colored hairs lower absorption of solar radiation by the leaf surface.
B) Light-colored hairs decrease the effectiveness of convective heat loss.
C) Light-colored hairs increase the effectiveness of latent heat transfer.
D) Pubescence results in a trade-off between two opposing heat exchange mechanisms.

Question 22

In the summer, leaves of E. farinosa show _______ pubescence than in the winter. The change in pubescence is an example of _______.

A) greater; adaptation
B) greater; acclimatization
C) greater; transpiration
D) less; acclimatization

Question 23

The zone of turbulent air flow close to the surface of an object is referred to as a _______ layer.

A) turbulence
B) protective
C) resistance
D) boundary

Question 24

Leaves that are comparatively _______ and _______ lose the most heat to wind because they have _______ boundary layers than other leaves.

A) small; smooth; thinner
B) small; smooth; thicker
C) large; rough; thinner
D) large; rough; thicker

Question 25

Which type of heat transfer is much more common in plants than in animals?

A) Output of infrared radiation
B) Evaporative heat loss
C) Metabolic heat generation
D) Reception of solar radiation

Question 26

Refer to the figure.
The figure shows the relationship between the outside temperature and the temperature of three animals. Which of these animals is an endotherm?

A) Animal A only
B) Animal B only
C) Animal C only
D) Both animal A and animal B

Question 27

Refer to the figure.


-The figure shows the relationship between the ambient temperature and the relative metabolic rates of a number of mammals. What is the lower critical temperature of an unclothed human?

A) About 6°C
B) About 11°C
C) About 20°C
D) About 26°C

Question 28

Refer to the figure.


-The figure shows the relationship between the ambient temperature and the relative metabolic rates of a number of mammals. How much of a difference is there between the lower critical temperature of a polar bear cub and the temperature at which its metabolic rate doubles?

A) About 10°C
B) About 18°C
C) About 36°C
D) About 55°C

Question 29

During cold periods, marmots enter a state of torpor in order to alter their lower critical body temperature. In comparison to the body temperature of a bear during its long winter sleep, the temperature of the marmot drops _______, and the duration of the torpor is _______ the bear's period of sleep.

A) much more; much shorter than
B) much less; much shorter than
C) to about the same extent; much shorter than
D) much more; about the same as

Question 30

Assuming that the body shape of an animal is at least somewhat spherical, a considerable decrease in body size would _______ the surface area-to-volume ratio, and the ability to exchange heat with the environment would _______.

A) increase; increase
B) increase; stay about the same
C) increase; decrease
D) decrease; increase

Question 31

The thermoneutral zone is the range of temperatures in which an active endotherm

A) can survive.
B) is operating at its basal metabolic rate.
C) is operating at its maximum metabolic rate.
D) is in torpor.

Question 32

If the body size of an ectotherm with a semi-spherical body shape were to increase considerably, the surface area-to-volume ratio would _______, and the animal's ability to exchange heat with the environment would _______.

A) increase; increase
B) increase; stay about the same
C) decrease; decrease
D) decrease; increase

Question 33

Which statement best supports the speculation that large dinosaurs may have had some degree of endothermy?

A) Their large bodies would have required some capacity for internal heat generation, even in cold conditions.
B) Because their surface area-to-volume ratio probably would not have allowed for enough heat exchange with their environment, they would have needed to generate some internal energy.
C) They would have had a high intake of nitrogen, which leads to endothermy.
D) We have evidence that they evolved from endothermic ancestors.

Question 34

Compared with large endotherms, small endotherms require _______ feeding rates, partly because they have a _______ surface area-to-volume ratio.

A) similar; similar
B) lower; lower
C) higher; higher
D) lower; higher

Question 35

Which sequence represents the correct ranking (from highest to lowest) of the metabolic rates of a 35-gram mouse, a 150-gram ectothermic lizard, and a 20-kg dog?

A) Mouse > lizard > dog
B) Mouse > dog > lizard
C) Dog > mouse > lizard
D) Lizard > dog > mouse

Question 36

The cells of a fish are about 0.85% salt. One liter of water is about 1,000 grams. Solution A contains 70 grams of salt in 5 liters of water, solution B contains 120 grams of salt in 10 liters of water, and solution C contains 50 grams of salt in 10 liters of water. Which solution(s) is(are) hyperosmotic relative to the fish's cells?

A) Solution A only
B) Solution B only
C) Both solution A and solution B
D) Both solution B and solution C

Question 37

The energy associated with dissolved solutes is called

A) matric potential.
B) osmotic potential.
C) pressure potential.
D) kinetic osmosis.

Question 38

Suppose that the osmotic potential of a system is -45 MPa. Pressure of 60 MPa is being exerted on the system and the matric potential is -40 MPa. What is the overall water potential of the system?

A) ‒145 MPa
B) ‒65 MPa
C) ‒25 MPa
D) +55 MPa

Question 39

System 1 has a water potential of ‒65 MPa. System 2 has a water potential of ‒45 MPa. System 3 has a water potential of 15 MPa. Water will flow from system _______ to system _______.

A) 1; 2
B) 2; 3
C) 3; 1
D) 2; 1

Question 40

Which soil type provides the best storage for biologically available water?

A) Sandy soil
B) Soil with large-sized particles
C) Fine-textured soil
D) Soil with a combination of sandy and fine particles

Question 41

Loss of _______ pressure results in wilting of nonwoody plants due to dehydration.

A) turgor
B) xyleic
C) osmotic
D) matric

Question 42

Which statement about roots and mycorrhizae is true?

A) Most land plants today take up water only through their roots.
B) Mycorrhizae are very good at absorption because they provide large amounts of surface area.
C) The ability of roots to take up water increases with thickness because thicker roots develop a water-resistant waxy coating.
D) Mycorrhizae allow less exploration of the soil for water and nutrients.

Question 43

Refer to the figure.
In the figure, as _soil declines over five days, what happens to 11ef0cf8_4c2f_5de3_baff_f734b72c3246_TBO1115_11_leaf at night?

A) It consistently drops lower than 11ef0cf8_4c2f_5de3_baff_f734b72c3246_TBO1115_11_soil.
B) It consistently is lower than 11ef0cf8_4c2f_5de3_baff_f734b72c3246_TBO1115_11_stem.
C) It takes longer to equilibrate with 11ef0cf8_4c2f_5de3_baff_f734b72c3246_TBO1115_11_soil.
D) Stomates stay open longer.

Question 44

Refer to the figure.


- In soil, there can be layers with more or less available water. In the figure, there is a lower water potential in shallow soils than in deep soils. Considering this scenario, what will the stem water potential be in the middle of the night and why?

A) -3.0 MPa because the plant will equilibrate with the lowest water potential.
B) -0.5 MPa because the plant will equilibrate with the highest water potential.
C) Between -3.0 MPa and -0.5 MPa because the plant will average across all available water.
D) Between -3.0 MPa and -0.5 MPa because some of the water from the deep soil layers will move through the roots and then into the dry, shallow soils.

Question 45

Refer to the figure.


-Plant ecophysiologists often measure the water potential of a plant at midnight to understand plant-soil-water relationships. If an investigator found that _stem was -2.0 MPa as shown in the figure, which statement would also be true?

A) 11ef0cf8_73d5_aa74_baff_b5862422f6cb_TBO1115_11_soil must be > -2.0.
B) 11ef0cf8_73d5_aa74_baff_b5862422f6cb_TBO1115_11_soil must be = -2.0.
C) 11ef0cf8_73d5_aa74_baff_b5862422f6cb_TBO1115_11_leaf must be > -2.0.
D) 11ef0cf8_73d5_aa74_baff_b5862422f6cb_TBO1115_11_air must be = -2.0.

Question 46

When a plant is using transpiration to cool off during the day, its stomates are _______ and its water potential is _______ negative than that of the soil. At night, the plant's water potential will be _______ that of the soil (assuming that the soil is receiving sufficient moisture).

A) open; more; roughly the same as
B) open; more; more positive than
C) open; less; roughly the same as
D) closed; less; more positive than

Question 47

As the soil dries out during a time of water stress, roots send _______, a hormonal signal, to the stomates, which decreases the extent of their opening and thus decreases water loss.

A) osmotic acid
B) cyclic AMP
C) glycerol
D) abscisic acid

Question 48

Which statement about kangaroo rats and their adaptations to the desert climate is false?

A) They have thicker and oilier skin than their non-desert relatives.
B) They have more sweat glands than their non-desert relatives.
C) Their metabolic processes supply much of their required water.
D) They minimize water loss in their urine and feces.

Question 49

The salinity of salmon is about 0.9%. Salmon living in water with 0.2% salinity would be _______ to the environment, and would tend to _______ water and _______ salts.

A) hypoxic; gain; lose
B) hypertensive; lose; gain
C) hyperosmotic; gain; lose
D) hypoosmotic; gain; lose

Question 50

You discover a new species of salamander. From your research, it appears that this species is highly endangered. You would like to establish a new breeding population of the salamanders in a protected area that is 300 km from the area where you first discovered them. There are no individuals of your new salamander currently living in the protected area. What kinds of data would you need to determine whether your salamander species could tolerate the conditions in the new park? Under which conditions would there be a good chance that the salamander would survive in the new park? What are two critical aspects that will determine whether a new salamander population could persist in the new area?

Question 51

You discover a new species of salamander. From your research, it appears that this species is highly endangered. You would like to establish a new breeding population of the salamanders in a protected area that is 300 km from the area where you first discovered them. There are no individuals of your new salamander currently living in the protected area. Imagine that you find that the environmental conditions in the new area differ from those at the discovery site. How would you determine whether the salamanders could survive in the new area, and what additional considerations would you have to take into account because of their likely status as an endangered species?

Question 52

Some plants respond to drought conditions by dropping their leaves. This reduces water loss, but can be risky for the plant. What conditions might cause a plant to fail to survive a drought, even if it dropped its leaves?

Question 53

You have just moved from Florida to Alaska and you are having trouble adjusting to this new, colder climate. What is one thing you can do to acclimate to the cold without relying on technology, tools, heat, shelter, or extra clothing? Describe how and why this change might help you acclimate to the colder temperatures. (You cannot go into torpor or hibernation, or migrate back to Florida!)

Question 54

A man, shipwrecked at sea, spends 12 hours floating in the ocean before washing up on the shore of a deserted island. This man's core body temperature has decreased due to the many hours spent in the cold ocean water, and he needs to warm up once he reaches the island. Here are two options for warming up:
Option 1: Siting on black rocks in the direct sunlight.
Option 2: Sheltering under a dense tree and using dry leaves as insulation.
Describe three different conditions in which sheltering under the dry leaves would provide more opportunity for heating up than sitting on the black rocks.

Question 55

A man, shipwrecked at sea, spends 12 hours floating in the ocean before washing up on the shore of a deserted island. By the time he reaches the island, he is severely dehydrated. He has several options for correcting his water balance: Assume that under normal conditions, his blood has 0.01 grams of salt per 1,000 grams of water, but under severe dehydration, the salt content increases to 0.5 grams per 1,000 grams of water.
• He could drink ocean water, which contains 37 grams of salt per 1,000 grams of water.
• He could drink from a puddle of rainwater that has been somewhat contaminated by sea water, but is not as salty as pure sea water and contains about 7 grams of salt per 1,000 grams of water.
• He could eat berries that contain 0.006 grams of salt per 1,000 grams of water, but the berries have been coated in salt spray that covers the outside of the berries with salt. For each 100 grams of berries, they are covered in 5.5 grams of salt.
• He could catch raindrops in his mouth when storms pass. He could manage to catch 10 drops per minute, and one milliliter of water contains 20 drops of water. However, he would also lose 300 milliliters of water per hour through respiration.
Which of the scenarios would provide him with the least amount of salt and the highest percentage of water most quickly? He can only use these options, but must come up with a creative solution to maximize his survival chances. What is his best course of action?

Question 56

A man, shipwrecked at sea, spends 12 hours floating in the ocean before washing up on the shore of a deserted island. The shipwrecked man has just finished collecting shellfish from the ocean and is lying on the beach absorbing solar radiation. A very large sea turtle crawls out of the ocean and suns itself on the same beach. Both individuals bask in the sun for 7 hours. If the temperature of the ocean is 10?C and the temperature of the sand is 30?C, how would you expect sand temperature to affect body temperature and how would body temperature change over time for both individuals? Create a graph that shows this pattern. Label the x and y axes. Draw a line that shows the expected change in temperature of the person over time and the expected change in temperature of the turtle over time. Label both lines.

Question 57

Mammals, birds, reptiles, and amphibians have circulatory systems driven by a pumping heart that transports nutrients, oxygen, and water throughout the body. Plants do not have a pumping heart, yet nutrients and water are transported, even in very large plants like trees. Why is it that plants do not need a pumping heart? What affects the rate at which water is transported through a plant?

Question 58

Many animals behave in ways that allow them to regulate their temperatures. Using the examples of the shipwrecked person and a kangaroo rat, what resource must both conserve? How are the actions of the person on the island and the actions of a kangaroo rat in the desert similar? How are they different in terms of their goals and mechanisms for managing their body temperature?

Question 59

Imagine that you want to cryogenically freeze yourself and maximize your chances of being brought back to life at a later time. How could you do it in such a way that you are protected from some of the consequences that might make resuscitation impossible? What would be a critical consequence of the cold temperatures that you would want to protect yourself against? What consequences might this have if you did not avoid it?

Question 60

Which of the following is an example of something that could be predicted with information on a species' "climate envelope"?

A) The reproductive rate of that species
B) The growth rate of the species
C) The survival rate of the species
D) The range that the species could potentially inhabit

Question 61

A mouse exposed to reduced levels of oxygen initially cannot run as fast as usual, but after a week its performance improves. This is an example of _______ to _______.

A) adaptation; hypoxia
B) acclimatization; hypothermia
C) adaptation; hypothermia
D) acclimatization; hypoxia

Question 62

An individual zooplankton can change its solute concentrations in response to a change in water salinity. This response is an example of _______ in the form of a(n) _______ adjustment.

A) adaptation; osmotic
B) acclimatization; osmotic
C) adaptation; turgor
D) acclimatization; stomatic

Question 63

Which organisms would most likely be able to tolerate the 90°C environments that occur in hot springs?

A) Bacteria
B) Insects
C) Fish
D) Mollusks

Question 64

Suppose that a horse is standing in partial shade. Solar radiation provides a net intake of energy of 42 milliwatts per minute, and infrared radiation provides an additional net input of 56 milliwatts per minute. Conductive and convective outputs of heat are a combined 308 milliwatts per minute. There is no detectable change in heat from evaporation. Assuming that the horse is maintaining a constant temperature, how much heat must it be generating (in milliwatts per minute)?

A) 98
B) 210
C) 266
D) 308

Question 65

If the temperature of a plant is 10°C and the ambient temperature is 14°C, there will be a net input of heat to the plant via

A) conduction.
B) convection.
C) evaporation.
D) conduction and convection

Question 66

Suppose a plant is receiving 190 units of heat per minute due to solar radiation, and 60 units of heat per minute due to infrared radiation. Eighty units per minute of solar radiation are reflected back by the leaves, and it emits 30 units of infrared radiation. It also loses 140 units of heat per minute through evapotranspiration. The temperature of a plant is not changing. Based on this, we can conclude that the combination of conduction and convection is resulting in a _______ of heat to the plant, and that its temperature is currently _______ the ambient temperature.

A) zero net change; the same as
B) net input; colder than
C) net output; warmer than
D) net output; colder than

Question 67

The condition known as pubescence, which refers to the presence of hair on the surface of leaves,

A) is often found in plants that live in particularly humid climates.
B) increases the effectiveness of convective heat loss.
C) lowers the absorption of solar radiation by leaf structures.
D) serves only as a deterrent to herbivory.

Question 68

Which animals are most likely to go into torpor during the winter?

A) Polar bears
B) Black bears
C) Marmots
D) Penguins

Question 69

Consider a plant that is transpiring. The highest water potential is in the _______ and the lowest water potential is in the _______.

A) surrounding soil; leaves
B) leaves; roots
C) leaves; surrounding soil
D) roots; leaves

Question 70

Suppose that the osmotic potential of a system is -55 MPa. The system is under tension, and the pressure potential exerted on the system is -40 MPa. The matric potential is -80 MPa. What is the overall water potential of the system?

A) ‒175 MPa
B) ‒135 MPa
C) +15 MPa
D) +175 MPa

Question 71

System 1 has a water potential of ‒2 MPa. System 2 has a water potential of -5 MPa. System 3 has a water potential of 0 MPa. Water will flow from system _______ to system _______.

A) 1; 2
B) 1; 3
C) 2; 3
D) 3; 1

Question 72

Compared with birds, amphibians have a _______ maximum resistance to and a _______ maximum tolerance for water loss.

A) higher; higher
B) higher; comparable
C) higher; lower
D) lower; higher

Question 73

Kangaroo rats adapted to the desert will

A) produce more sweat during the hottest part of the day to reduce their body temperature.
B) produce water through their metabolizing of food.
C) rely on behavioral strategies to minimize water loss.
D) Both b and c

Question 74

The cells of a fish are about 0.8% salt. One liter of water is about 1,000 grams. Solution A contains 70 grams of salt in 20 liters of water, solution B contains 120 grams of salt in 10 liters of water, and solution C contains 50 grams of salt in 10 liters of water. Which solution is hyperosmotic to the fish?

A) Solution A only
B) Solution B only
C) Both solution A and solution B
D) Both solution B and solution C