Question 1

The metamorphosis of a tadpole to an adult frog involves a thorough reconstruction of the animal's body. All of the structural and physiological changes must be complete or the frog will not survive this transformation. Which type of regulation would ensure that the animal completed its transformation?
A) positive feedback
B) negative feedback
C) feedback inhibition
D) enzymatic catalysis

Accepted Answer

The answer of The metamorphosis of a tadpole to an...

Question 2

The migratory eel, Anguilla rostrata, is born and lives the juvenile (immature)part of its life in a freshwater environment, but then migrates thousands of miles through the ocean as an adult in order to breed. These eels are known to regulate their internal water and salt balance. What adaptations would you expect this eel to have in order to transition from fresh water to salt water at these two life stages?
A) The juvenile eels would be better at removing salt from their bodies compared to adults.
B) The adult eels would be better at removing salt from their bodies compared to juveniles.
C) The juvenile eels would spend energy keeping water in their bodies.
D) The adult eels would spend energy keeping salt in their bodies.

Accepted Answer

Adult eels need to be able to transition from fresh water to salt water, so they would have adaptations to help them remove salt from their bodies. Juveniles are not yet mature and have not yet made the transition, so they would not have strong adaptations for removing salt. Therefore, choice B is the best answer.

Question 3

What would be an advantage for an animal that conforms to a changing environmental condition, such as temperature?
A) The animal's internal temperature would remain constant, even though the external temperature had changed.
B) The animal's internal temperature would change opposite to the change in the external temperature.
C) The animal would spend more time looking for food.
D) The animal would spend less energy regulating its internal temperature.

Accepted Answer

The answer of What would be an advantage for an...

Question 4

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.

Accepted Answer

A sphere has the smallest surface area to volume ratio of any shape, which means rounding the clay up into a sphere will decrease its surface area relative to its volume. The other options all increase the surface area relative to the volume by changing the shape in a way that increases the total surface area of the clay.

Question 5

When the body's blood glucose level rises, the pancreas secretes insulin and, as a result, the blood glucose level declines. When the blood glucose level is low, the pancreas secretes glucagon and, as a result, the blood glucose level rises. Such regulation of the blood glucose level is the result of ________.
A) catalytic feedback
B) positive feedback
C) negative feedback
D) protein-protein interactions

Accepted Answer

The regulation of blood glucose through the secretion of insulin and glucagon is an example of negative feedback. Negative feedback occurs when a change in a variable (such as blood glucose level) triggers a response that opposes or reverses the initial change, thus maintaining homeostasis. In this case, the secretion of insulin lowers the blood glucose level when it is high, and the secretion of glucagon raises the blood glucose level when it is low, both working to maintain a stable blood glucose level.

Question 6

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

Accepted Answer

When the elephants spray water over their bodies with their trunks, evaporation occurs. As the water evaporates from their skin, it absorbs heat from the elephant's body, resulting in a cooling effect.

Question 7

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

Accepted Answer

Ectotherms have a lower metabolic rate and lower energy requirements compared to endotherms, which invest a significant amount of energy in temperature regulation. This makes ectotherms better adapted to surviving extended periods of food deprivation in a cool environment because they do not have to expend significant amounts of energy to maintain their body temperature.

Question 8

The metabolic rate of an animal is most accurately determined by ________.
A) the amount of work done by an animal
B) the amount of food consumed during a meal
C) the amount of carbon dioxide produced by an animal in a given time.
D) the amount of energy used by an animal in a given time

Accepted Answer

The answer of The metabolic rate of an animal is...

Question 9

To prepare flight muscles for use on a cool morning, hawkmoths ________.
A) relax the muscles completely until after they launch themselves into the air
B) decrease their standard metabolic rate
C) rapidly contract and relax these muscles to generate metabolic warmth
D) reduce the metabolic rate of the muscles to rest them before flight

Accepted Answer

Hawkmoths rapidly contract and relax their flight muscles to generate metabolic warmth before takeoff on a cool morning. This process is known as shivering thermogenesis and helps them reach their optimal body temperature for flight.

Question 10

Which organ system is responsible for protection against injury, infection, and dehydration?
A) Reproductive system
B) Excretory system
C) Skeletal system
D) Integumentary system

Accepted Answer

The integumentary system, which includes the skin, hair, and nails, is responsible for protecting the body against injury, infection, and dehydration. The skin acts as a physical barrier against external threats, while also producing oils and sweat that help to maintain hydration and prevent the growth of harmful microorganisms.

Question 11

Bone consists of ________.
A) a mixture of hardened collagen and minerals.
B) chondroitin sulfate secreted by chondrocytes.
C) many columnar epithelial cells packed together.
D) hardened fibrous connective tissue.

Accepted Answer

Bone is made up of a combination of hardened collagen (a protein) and minerals such as calcium and phosphate. This gives bone its strength and hardness.

Question 12

You discover a new species of bacteria that grows in aquatic environments with high salt levels. While studying these bacteria, you note that their internal environment is similar to the salt concentrations in their surroundings. You also discover that the internal salt concentrations of the bacteria change as the salt concentration in their environment changes. The new species can tolerate small changes in this way, but dies from large changes because it has no mechanism for altering its own internal salt levels. What type of homeostatic mechanism is this species using to regulate its internal salt levels?
A) conformation
B) regulation
C) integration
D) assimilation

Accepted Answer

The bacteria use a conformation mechanism to regulate their internal salt levels, meaning that their internal salt levels change in response to the salt concentration in their environment. They do not have a regulation mechanism, which would involve actively controlling their internal salt levels, or an integration mechanism, which would involve coordinating various physiological processes to maintain a stable internal environment. Assimilation is not a relevant concept in this context.

Question 13

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

Accepted Answer

Ectothermic organisms rely on external sources of heat to regulate their body temperature. In deep ocean environments, the temperature is relatively stable, giving sea stars no behavioral options to adjust their body temperature. In contrast, bass in a farm pond can move to different areas of the pond to adjust their body temperature, hummingbirds can fly to different locations to find warmer or cooler temperatures, and honeybees can cluster together to generate heat in their hive.

Question 14

Chum salmon (Oncorhynchus keta)are born in freshwater environments and then migrate to the sea. Near the end of their lives, they return to the freshwater stream where they were born to spawn. In fresh water, water constantly diffuses into the body and ions are lost from the body. In salt water, body water diffuses out of the body and excess ions are gained from the water. A salmon's gills have special cells to pump salt in or out of the body to maintain homeostasis. In response to the salmon's moves between fresh water and salt water, some cells in the gills are produced and others are destroyed. These changes made in the cells of the gills during the lifetime of an individual salmon are an example of which of the following?
A) evolution
B) trade-off
C) acclimatization
D) adaptation

Accepted Answer

The changes made in the cells of the salmon's gills in response to moving between fresh water and salt water are an example of acclimatization, which is the ability of an individual organism to adjust to changes in its environment. This is not an example of evolution because it does not involve genetic changes that are passed on to offspring. It is also not a trade-off because there is no clear cost-benefit analysis involved. Adaptation is a broader term that can include both genetic changes and physiological acclimatization, but in this case, acclimatization is the more specific term that accurately describes the changes in the gill cells.

Question 15

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.

Accepted Answer

The mouse has a higher surface-area-to-volume ratio than the elephant, meaning it has more surface area in proportion to its volume. This allows for a greater rate of heat loss through the skin, so the mouse will cool down faster than the elephant in the shade.

Question 16

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.

Accepted Answer

The statement that 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 is true. This size-mass relationship affects the amount of food and oxygen an animal requires, the amount of heat and waste it produces, and its ability to regulate its internal environment. As animals get larger, it becomes more difficult for them to exchange materials with their environment, which can limit their growth and survival.

Question 17

An example of a properly functioning homeostatic control system is seen when ________.
A) the core body temperature of a runner rises gradually from 37°C to 45°C
B) the kidneys excrete salt into the urine when dietary salt levels rise
C) a blood cell shrinks when placed in a solution of salt and water
D) the blood pressure increases in response to an increase in blood volume

Accepted Answer

This is an example of negative feedback, where the body senses an increase in salt levels and responds by excreting salt in order to maintain a stable internal environment. Option A is incorrect because the body temperature should not rise to 45°C which is potentially life-threatening. Option C is a case of osmosis where the concentration gradient causes the cell to shrink but it does not involve any feedback mechanisms. Option D is incorrect because an increase in blood pressure is not a proper response to an increase in blood volume, indicating a dysfunctional homeostatic control system.

Question 18

The body's automatic tendency to maintain a constant and optimal internal environment is termed as ________.
A) balanced equilibrium
B) physiological chance
C) homeostasis
D) static equilibrium

Accepted Answer

Homeostasis refers to the ability of the body to maintain a relatively stable internal environment despite changes in external conditions. This process involves a series of physiological and biochemical mechanisms that work together to regulate various bodily functions, such as temperature, pH, blood sugar levels, and electrolyte balance. This ensures that the body is able to function properly and efficiently, even when faced with environmental stressors or other challenges. Balanced equilibrium, physiological chance, and static equilibrium do not accurately describe this process.

Question 19

If a person were to travel to a time zone that was several hours ahead of their own, they may experience tiredness known as jet lag. Jet lag is due to a disruption of ________.
A) homeostasis
B) circadian rhythm
C) body temperature
D) nerve impulses

Accepted Answer

Jet lag is caused by a disruption of the body's circadian rhythm, which is responsible for regulating sleep-wake cycles and other physiological processes. When traveling to a different time zone, the body's internal clock may not immediately adjust to the new schedule, leading to feelings of tiredness and poor sleep.

Question 20

What is the name of the epithelial cell surface that faces the outside of an organ?
A) apical
B) basal
C) interstitial
D) lumen

Accepted Answer

The answer of What is the name of the epithelial...

Quiz 40: Basic Principles of Animal Form and Function

What would be an advantage for an animal that conforms to a changing environmental condition, such as temperature?

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?

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

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 ________.

The metabolic rate of an animal is most accurately determined by ________.

To prepare flight muscles for use on a cool morning, hawkmoths ________.

Which organ system is responsible for protection against injury, infection, and dehydration?

Bone consists of ________.

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 ________.

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?

Which of the following is a true statement about body size and physiology?

An example of a properly functioning homeostatic control system is seen when ________.

The body's automatic tendency to maintain a constant and optimal internal environment is termed as ________.

If a person were to travel to a time zone that was several hours ahead of their own, they may experience tiredness known as jet lag. Jet lag is due to a disruption of ________.

What is the name of the epithelial cell surface that faces the outside of an organ?