Question 1

Explain why many prey species reduce activity when they detect predators but have high activity when they do not detect predators.

Accepted Answer

The answer of Explain why many prey species reduce activity...

Question 2

Consider the figure, which shows how Virginia pepperweed responds to herbivores. Which of the following conclusions can we make solely using the data shown?  I. Plants increased glucosinolate production when aphids were present.
II) Plants with more glucosinolate and trichomes had fewer aphids.
III) Producing glucosinolate and trichomes reduced plant fitness when aphids were absent.

Accepted Answer

From the graph, we can see that when aphids were present, the production of glucosinolate increased. This supports conclusion I. We can also see that plants with more glucosinolate and trichomes had fewer aphids, which supports conclusion II. However, we cannot make any conclusions about the effect of producing glucosinolate and trichomes on plant fitness when aphids are absent, so we cannot support conclusion III. Therefore, the correct answer is D: I and II only.

Question 3

One cost of self-fertilization in the absence of mates is

Accepted Answer

Self-fertilization increases the chances of mating between closely related individuals, which can lead to inbreeding depression.

Question 4

Refer to the figure to answer this question.  Describe the phenotypic plasticity of common pond snails in the absence of mates, and explain the costs and benefits of that phenotypic plasticity.

Accepted Answer

The answer of Refer to the figure to answer this...

Question 5

Torpor is beneficial to animals because it

Accepted Answer

Torpor is a state of decreased activity and metabolic rate that allows animals to conserve energy. This is especially beneficial for animals that are unable to find food or live in environments where it is difficult to survive, such as during winter months or droughts. Torpor also helps animals survive extreme temperatures by reducing energy expenditure and preventing them from overheating or freezing.

Question 6

Describe how a desert iguana can survive high summer temperatures.

Accepted Answer

The answer of Describe how a desert iguana can survive...

Question 7

When humans move from low elevations to high elevations, it typically takes one or more weeks for their bodies to improve their ability to carry oxygen. This is an example of

Accepted Answer

The process described in the question is acclimation, which refers to the physiological changes that occur in an organism in response to a change in its environment, such as a change in altitude. It takes time for the body to adjust to the decrease in oxygen availability at high elevations, and this process of acclimation improves the body's ability to carry oxygen. The other options are not relevant to the scenario described in the question - microhabitat use refers to an organism using a specific small-scale habitat within a larger habitat, aestivation refers to a state of reduced metabolic activity in response to high temperatures or drought, and migration refers to the seasonal movement of organisms from one region to another.

Question 8

Tigriopus copepods living in ocean tide pools are subject to frequent changes in salt concentrations. In response to these drastic changes in salinity, Tigriopus copepods change the amount of amino acids in their bodies, which allows the osmotic potential of their body fluids to match that of the tide pool. This is an example of

Accepted Answer

This is an example of acclimation, as the Tigriopus copepods are changing their physiological response to the changed salinity levels in their environment.

Question 9

If a goldfish is acclimated at 25°C, at which temperature would we expect the fish to swim fastest?

Accepted Answer

Fish are ectothermic, which means their body temperature is determined by the temperature of their surroundings. As a result, their metabolic rate and swimming speed increase with temperature, up to a certain point where it becomes too hot and they start to suffer heat stress.

Goldfish are native to temperate regions of Asia and are adapted to water temperatures that fluctuate throughout the year. They can tolerate a wide range of temperatures, from about 5°C to 30°C, but their optimal range for growth and reproduction is between 20°C and 25°C.

Therefore, we would expect the goldfish to swim fastest at the temperature it is acclimated to, which is 25°C. At temperatures below that range, the fish's metabolic rate would slow down and its swimming performance would decrease. At temperatures above that range, the fish's metabolic rate would increase but its swimming performance would eventually decline due to oxygen limitation, muscle fatigue, and other physiological and behavioral factors.

Question 10

Based on the figure, describe the phenotypic trade-offs of a fish being acclimated to 25°C compared to a fish acclimated to 5°C.

Accepted Answer

The answer of Based on the figure, describe the phenotypic...

Question 11

The phenotypic plasticity that allows a copepod to survive being moved from salt water to fresh water is similar to the phenotypic plasticity of a human moved from low elevation to high elevation because both are

Accepted Answer

The ability of a copepod to survive in fresh water is due to its physiological phenotypic plasticity, specifically the ability to regulate ion balance. Similarly, humans who move to high elevations undergo physiological changes in their blood cell production and oxygen transport, demonstrating physiological phenotypic plasticity. Both copepods and humans are able to adapt to new environments through changes in their physiological processes.

Question 12

Over the course of a day, a snake will move from place to place to reach its preferred body temperature. This is an example of

Accepted Answer

Microhabitat use refers to the ways in which organisms move within their environment to optimize their survival and reproduction. In this case, the snake is moving in order to reach its preferred body temperature, which is an example of microhabitat use as it represents a way in which the snake is optimizing its survival in its environment. Acclimation generally refers to the process by which organisms become better adapted to changing environmental conditions, but it does not necessarily involve movement. Aestivation refers to a type of dormancy that some animals enter during hot, dry conditions, and migration refers to the movement of animals from one area to another in response to seasonal changes or other environmental conditions.

Question 13

Which of the following are phenotypically plastic responses of plants to reduced water availability?
I. develop trichomes and produce more glucosinolate
II. close stomata in leaves
III. increase the root/shoot ratio

Accepted Answer

I is not a phenotypically plastic response to reduced water availability. Developing trichomes and producing more glucosinolate are adaptations to deter herbivores, not a direct response to reduce water availability. 
II and III are both phenotypically plastic responses to reduce water availability. Closing stomata helps to reduce water loss through transpiration, while increasing the root/shoot ratio helps to increase water uptake and reduce water loss. Therefore, the correct answer is E) II and III only.

Question 14

What form of dormancy do mammals use to conserve energy and survive seasons during which they are unable to obtain food?

Accepted Answer

Mammals use hibernation to conserve energy and survive seasons during which they are unable to obtain food. During hibernation, their metabolic rate, heart rate, and breathing rate decrease dramatically, allowing them to survive on their stored fat reserves until food becomes available again. Diapause is a form of dormancy used by insects and other invertebrates to survive unfavorable environmental conditions, while torpor is a short-term form of hibernation used by some mammals to conserve energy during times when food is scarce. Aestivation is a form of dormancy used by some animals to survive hot or dry seasons.

Question 15

What types of plants and animals are able to reproduce even if they cannot find a mate?

Accepted Answer

Hermaphrodites have both male and female reproductive organs, so they are able to reproduce without a mate through self-fertilization.

Question 16

The figure shows plant growth responses to variation in availability of water. If this is an example of adaptive phenotypic plasticity, how would we expect the root-to-shoot ratio to be related to fitness?

Accepted Answer

The answer of The figure shows plant growth responses to...

Question 17

Why is it beneficial for birds and mammals with high surface-area-to-volume ratios to reduce their body temperature for short periods?

Accepted Answer

Birds and mammals with high surface-area-to-volume ratios lose heat more rapidly than larger animals, therefore they must consume more energy to generate heat. By reducing their body temperature intermittently, they can save energy that would be consumed producing body heat. This strategy is known as torpor and is often used by small or hibernating animals, as well as birds during migration.

Question 18

A specific location within the area where an animal lives and typically contains more favorable abiotic conditions than other locations in the area is a(n)

Accepted Answer

A microhabitat is a specific location within an area that contains more favorable abiotic conditions than other locations in the area. This can include areas with more or less sunlight, moisture, or shelter, and can vary depending on the specific needs of the animal. Torpor is a physiological state of decreased activity and metabolism, not a location. Acclimation refers to an organism's ability to adjust to changing environmental conditions, but does not necessarily relate to a specific location. Climate refers to the long-term patterns of temperature, precipitation, and other weather variables in an area, not a specific location within it.

Question 19

During the course of two generations, monarch butterflies move from southern Canada to Mexico, spend the winter in Mexico, and then return to southern Canada. This is an example of

Accepted Answer

Monarch butterflies' seasonal movement is a classic example of migration. They travel thousands of miles each year to escape the cold temperatures of their northern breeding grounds and overwinter in the warmth of central Mexico. During the spring, they return north to lay their eggs again.

Question 20

Many Arctic animals accumulate fat as an energy reserve that allows them to survive winter when food is difficult to obtain. This strategy is an example of

Accepted Answer

Accumulating fat as an energy reserve is an example of storage, where the animals store energy in their bodies to use later when food is scarce. Migration involves the animals moving to a different location where food is more readily available, dormancy refers to a state of inactivity, and diapause is a type of suspended development seen in some insects.

Quiz 4: Adaptations to Variable Environments