Question 1

Which term best describes an animal that,although generating a significant amount of heat through metabolism,nonetheless does not maintain a constant body temperature?
A)homeothermic endotherm
B)heterothermic ectotherm
C)homeothermic ectotherm
D)heterothermic endotherm

Accepted Answer

The answer of Which term best describes an animal that,although...

Question 2

Torpor has evolved in several high-latitude species even though it is energetically expensive.Why does this adaptation require a large energy input for those species that utilize this function?
A)These animals expend a great deal of metabolic energy to maintain their body temperature as the ambient temperatures drop.
B)It takes a great deal of energy to stay alive when the body temperature drops to near ambient levels.
C)During torpor,animals undergo excessive shivering to maintain their body temperature.
D)Animals in torpor lower their body temperature dramatically and require a great deal of energy to bring the body temperature back up to normal.

Accepted Answer

Animals in torpor lower their body temperature dramatically and require a great deal of energy to bring the body temperature back up to normal.

Question 3

Structure-function correlations exist throughout nature at all levels of organization,from the cellular level to systems level.Keeping this in mind,you visualize a cell under a microscope and it contains a lot of rough endoplasmic reticulum.What might you hypothesize the primary function of the cell to be?
A)energy storage
B)hormone (protein)synthesis and release
C)conduction of electrical signals
D)participation in the immune response

Accepted Answer

The answer of Structure-function correlations exist throughout nature at all...

Question 4

Gills serve multiple functions in fish in addition to gas exchange.Given the large surface area of gills with lamellae,what is the most likely explanation for why crucian carp cover protruding lamellae in their gills when levels of oxygen are normal?
A)to prevent loss of heat to the surrounding water
B)to prevent loss of ions to the surrounding water
C)to prevent protein loss to the surrounding water
D)to prevent loss of oxygen to the surrounding water

Accepted Answer

Covering the lamellae helps prevent the loss of ions to the surrounding water, maintaining osmotic balance.

Question 5

Which of the following explanations for brown adipose tissue explains why infant humans and some small mammals have this tissue type?
A)This tissue allows for the conversion of fats directly into heat without the production of ATP.
B)This tissue can convert ATP into heat energy instead of using it for muscle contraction and other energy-requiring processes.
C)This tissue stores more heat than other types of fat because of its darker color.
D)This tissue type has less water than other adipose tissues and thus has less evaporative cooling.

Accepted Answer

The answer of Which of the following explanations for brown...

Question 6

What is the main reason that a person sitting on the beach with an air temperature of 15°C loses heat less rapidly than when immersed in lake water at 15°C?
A)Water conducts heat more efficiently than air does.
B)Water evaporates,and heat is lost to evaporation.
C)Metabolic heat production is greater in air than in water.
D)Air is a poor insulator.

Accepted Answer

Water conducts heat more efficiently than air, which means that heat will be transferred away from the body more rapidly when a person is immersed in water at the same temperature as the air.

Question 7

Which principle of heat exchange is the most important explanation for why birds look larger in colder weather because they fluff their feathers?
A)Fluffing feathers results in less cooling by radiation since feathers emit less infrared radiation than other tissues do.
B)Fluffing decreases the amount of heat lost by conduction when the bird makes contact with cold objects in its environment.
C)Fluffing creates a pocket of air near the bird that acts as insulation.
D)Fluffing decreases the surface area/volume ratio,thus decreasing the amount of heat lost to the environment.

Accepted Answer

Fluffing feathers creates a pocket of air near the bird that acts as insulation, reducing the rate of heat loss to the environment. This is known as the principle of insulation, which states that thicker or more voluminous materials reduce the rate of heat transfer because they create a barrier that inhibits the transfer of heat from one side to another. This results in the bird looking larger in colder weather as it fluffs its feathers, as the pockets of air created by the fluffing make the bird appear bulkier.

Question 8

Multicellular organisms are limited by size and,thus,ways to increase surface area of a structure are often advantageous.Which of the following pairs of words best describes ways to increase the surface area of a structure?
A)folding and branching
B)shortening and converging
C)flattening and converging
D)shortening and flattening

Accepted Answer

Folding and branching both increase the surface area of a structure without increasing its overall size. Shortening and converging would decrease surface area, while flattening and converging would not necessarily increase surface area. Shortening and flattening may increase surface area in certain cases, but folding and branching are more common ways to achieve this.

Question 9

Choose the statement below that is TRUE regarding thermoregulation strategy.
A)An Atlantic salmon regulates its body temperature to match the surrounding air temperature.
B)A rooster's internal temperature is kept strictly at 39°C.
C)An ant's body temperature fluctuates with the surrounding environment.
D)A kangaroo's body temperature conforms to the surrounding environment.

Accepted Answer

Ants are ectothermic, meaning their body temperature changes with the environment.

Question 10

Which of the following is an example of a structure that has an increased surface area for absorption?
A)a cow's digestive tract consisting of 3 stomachs
B)an earthworm's segmented body
C)a cheetah's large nostrils
D)a human's lungs with many thin-walled alveoli

Accepted Answer

The lungs have many thin-walled alveoli which increase the surface area for gas exchange and absorption of oxygen into the bloodstream.

Question 11

You are a doctor and you are given the files of two patients who are identical twin brothers: Patient #1: 25 year old male,30% muscle mass,70% fat content,37 degrees C internal temperature
Patient #2: 25 year old male,70 % muscle mass,30% fat content,37 degrees C internal temperature
If you are told that both patients are equally active and are completely healthy,which of the following assumptions can we make regarding the metabolic rates of the brothers?
A)Patient # 1 and Patient # 2 likely have the same metabolic rate.
B)Patient # 1 likely has a higher metabolic rate than Patient # 2.
C)Patient # 1 likely has a lower metabolic rate than Patient # 2.

Accepted Answer

Patient #2, with higher muscle mass, likely has a higher metabolic rate than Patient #1, as muscle tissue burns more calories than fat tissue.

Question 12

Many types of ectothermic animals can be seen lying out in the sun on a warm,sunny day.What is the primary mechanism by which the animal warms itself during this activity?
A)conduction
B)convection
C)radiation
D)evaporation

Accepted Answer

Ectothermic animals warm themselves primarily through radiation, which involves absorption of heat from the sun's rays. This is why they commonly bask in the sun on warm days. Conduction and convection involve transfer of heat through contact with a heat source or movement of a fluid, respectively, and are less important for ectothermic animals. Evaporation is a cooling mechanism rather than a method of warming.

Question 13

After you eat a meal,blood glucose concentration increases.Insulin is released from the pancreas to restore blood glucose concentration by facilitating the uptake of glucose by cells and stimulating the conversion of glucose to glycogen.What homeostatic mechanism is this an example of?
A)positive feedback
B)negative feedback
C)neutralizing feedback
D)feedback inhibition

Accepted Answer

This is an example of negative feedback. When blood glucose concentration increases after a meal, insulin is released to bring it back to normal levels. This is a self-regulating mechanism that works to maintain homeostasis.

Question 14

Which of the following scenarios illustrates the physiological response of acclimatization?
A)Genetic changes have occurred in populations that have lived high in the Alps for many generations that allow individuals in these populations to cope with an environment with low oxygen.
B)Desert-dwelling plants such as the cactus have developed long root systems to ensure that they get enough water.
C)A dog sheds its thick winter fur for a lighter coat of fur when the temperature warms in the spring and summer.

Accepted Answer

Acclimatization refers to the physiological adjustments an organism makes in response to changes in its environment, such as a dog shedding its winter fur for a lighter coat in warmer temperatures.

Question 15

Natural selection has contributed to the wide variety of beak morphologies exhibited by the Galápagos Island finches.A correlation exists whereby beak morphology suggests the primary food source of the finch.Which physiological response listed below best describes the variety of beak morphologies seen in these finches?
A)adaptation
B)acclimation
C)acclimatization

Accepted Answer

Natural selection has caused the finches to adapt to the different food sources available on the Galápagos Islands, leading to the variety of beak morphologies seen in the population.

Question 16

Scientists have performed studies to show that having a fever is adaptive.Which of the following observations in an ectotherm would be consistent with this conclusion?
A)An ectotherm with a fever will tend to stay warm by covering with a blanket.
B)An ectotherm with a fever will seek out cooler environments,like a tub of cool water.
C)An ectotherm with a fever will tend to decrease overall activity levels in order to keep from overheating.
D)An ectotherm will develop a fever after an infectious organism has been destroyed in order to speed healing.

Accepted Answer

Ectotherms rely on external heat sources to regulate their body temperature. If having a fever is adaptive, an ectotherm with a fever would seek warmth to raise its body temperature, consistent with the behavior of covering with a blanket to stay warm.

Question 17

Countercurrent multiplier systems are common in animals.Which of the following schematics best represents a countercurrent exchanger?
A) 
B) 
C) 
D)

Accepted Answer

Countercurrent exchangers involve two fluid flows moving in opposite directions, such as blood and water in the gills of fish. Option B shows two arrows moving in opposite directions, which is the most accurate representation of a countercurrent exchanger. Options A, C, and D do not show fluid flows moving in opposite directions.

Question 18

Which of the following statements comparing endotherms and ectotherms is false?
A)Mitochondrial density and enzyme activity are 3-4 times higher in the cells of endotherms than in the cells of ectotherms of similar size.
B)Ectotherms can use more of their energy intake for reproduction than endotherms can.
C)Endotherms and ectotherms have about the same mass-specific metabolic rate.
D)Both endotherms and ectotherms exchange heat with the environment through convection,conduction,radiation,and evaporation.
E)B,C,and D are all false.

Accepted Answer

Endotherms generally have a higher mass-specific metabolic rate compared to ectotherms, not the same.

Quiz 41: Animal Form and Function

Which term best describes an animal that,although generating a significant amount of heat through metabolism,nonetheless does not maintain a constant body temperature?

Torpor has evolved in several high-latitude species even though it is energetically expensive.Why does this adaptation require a large energy input for those species that utilize this function?

Gills serve multiple functions in fish in addition to gas exchange.Given the large surface area of gills with lamellae,what is the most likely explanation for why crucian carp cover protruding lamellae in their gills when levels of oxygen are normal?

Which of the following explanations for brown adipose tissue explains why infant humans and some small mammals have this tissue type?

What is the main reason that a person sitting on the beach with an air temperature of 15°C loses heat less rapidly than when immersed in lake water at 15°C?

Which principle of heat exchange is the most important explanation for why birds look larger in colder weather because they fluff their feathers?

Multicellular organisms are limited by size and,thus,ways to increase surface area of a structure are often advantageous.Which of the following pairs of words best describes ways to increase the surface area of a structure?

Choose the statement below that is TRUE regarding thermoregulation strategy.

Which of the following is an example of a structure that has an increased surface area for absorption?

Many types of ectothermic animals can be seen lying out in the sun on a warm,sunny day.What is the primary mechanism by which the animal warms itself during this activity?

After you eat a meal,blood glucose concentration increases.Insulin is released from the pancreas to restore blood glucose concentration by facilitating the uptake of glucose by cells and stimulating the conversion of glucose to glycogen.What homeostatic mechanism is this an example of?

Which of the following scenarios illustrates the physiological response of acclimatization?

Scientists have performed studies to show that having a fever is adaptive.Which of the following observations in an ectotherm would be consistent with this conclusion?

Countercurrent multiplier systems are common in animals.Which of the following schematics best represents a countercurrent exchanger?

Which of the following statements comparing endotherms and ectotherms is false?