Question 1

You have a cube of modelling 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 ratio of surface area to volume among all geometric shapes, so rounding the clay up into a sphere will decrease its surface area relative to its volume.

Question 2

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 species is using a conformation homeostatic mechanism, as it does not actively regulate its own internal salt concentrations, but rather conforms to the concentrations of its environment.

Question 3

An example of an ectothermic organism that has few or no behavioural options when it comes to its ability to adjust its body temperature is a ________.
A) star fish living deep in the ocean
B) bass living in a farm dam
C) hummingbird flying through a plain
D) honeybee in a hive on a rural farm

Accepted Answer

Ectothermic organisms rely on external sources of heat to regulate their body temperature. As a starfish living deep in the ocean, it does not have the option to easily move to a warmer or cooler location, as the temperature of the water around it is relatively constant. Therefore, it is limited in its ability to adjust its body temperature, making it a good example of an ectothermic organism with few or no behavioural options in this regard.

Question 4

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 will cool down faster because it has a higher surface-area-to-volume ratio, meaning it has more surface area relative to its volume, allowing for more efficient heat loss through its skin. Additionally, the smaller mass of the mouse means less heat is retained, further aiding in its ability to cool down faster.

Question 5

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

The kidneys excreting salt into the urine when dietary salt levels rise is an example of a properly functioning homeostatic control system. The body is regulating the salt levels in the blood by removing excess through urine excretion. Options A and D describe situations where the body's control system is not functioning properly, as excessively high core body temperature and blood pressure can both lead to negative health effects. Option C is simply an example of osmosis, not a homeostatic control system.

Question 6

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 circadian rhythm, which is the internal biological clock that regulates bodily functions such as sleep-wake cycles, hunger, and body temperature. Traveling to a different time zone can disrupt this rhythm, leading to feelings of fatigue and a lack of alertness.

Question 7

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 is the term used to describe the body's ability to maintain a stable and optimal internal environment. This involves controlling various physiological parameters such as body temperature, blood sugar levels, and pH balance, among others. Homeostasis is essential for the survival and proper functioning of the body's cells, tissues, and organs.

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 metabolic rate refers to the amount of energy used by an animal in a given time. Therefore, the most accurate way to measure metabolic rate would be to measure the amount of energy used by the animal. Options A and B could be influenced by factors other than metabolic rate and would not give an accurate measure. Option C could be used to estimate metabolic rate, but it would not be as accurate as measuring the actual energy usage.

Question 9

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

The adult eels would need to be better at removing salt from their bodies compared to juveniles in order to adapt to the saltier ocean environment. The juvenile eels would primarily need to spend energy keeping water in their bodies to maintain their internal water and salt balance in freshwater environments.

Question 10

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 flight. This is known as shivering thermogenesis and is a common adaptation in insects and other animals that need to warm up their muscles before use on a cool morning. Choice A is incorrect because relaxing the muscles completely would not prepare them for flight. Choice B is incorrect because decreasing the metabolic rate would actually make the muscles colder and less prepared for flight. Choice D is incorrect because reducing the metabolic rate would be counterproductive to preparing the muscles for use.

Question 11

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) acclimatisation
D) adaptation

Accepted Answer

The changes made in the cells of the gills during the lifetime of an individual salmon are an example of acclimatization, which refers to a reversible physiological adjustment to a changing environment. It is not an example of evolution, which involves genetic changes occurring over many generations. Trade-off implies a balance between two or more benefits and costs, which is not relevant in this context. While the changes in the salmon's gills can be considered an adaptation, this term usually refers to a genetic change that enhances an organism's survival and reproduction in a particular environment, rather than a physiological response to a changing environment.

Question 12

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 by the pancreas involves a negative feedback loop, where the secretion of insulin and glucagon is triggered by changes in blood glucose levels that act to reverse or counteract those changes. This helps to maintain a stable blood glucose concentration within a narrow range. Catalytic feedback and protein-protein interactions do not accurately describe this process, while positive feedback would lead to a runaway increase or decrease in blood glucose levels.

Question 13

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

As an animal's size increases, its volume and weight increase more rapidly than its surface area. This creates challenges for large animals in terms of acquiring enough oxygen and nutrients and eliminating waste products efficiently. Small animals, on the other hand, have less distance for nutrients and gases to diffuse across their tissues, making it easier for them to meet their metabolic needs. Option A is incorrect because the relationship between an animal's mass and its requirements for food, oxygen, heat, and waste is proportional, not inversely proportional. Option B is incorrect because an animal's metabolic rate is not independent of its volume; larger animals have lower metabolic rates per unit of body mass. Option D is incorrect because the relationship between an animal's volume and the amount of waste it produces is not linear; as an animal's size increases, its waste production increases more rapidly than its volume.

Question 14

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 15

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

Evaporation is occurring as the water on the surface of the elephant's skin evaporates, it absorbs heat from the elephant's body, thereby cooling it down.

Question 16

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, nails, and glands, is responsible for protecting the body against injury, infection, and dehydration. The skin acts as a physical barrier, preventing pathogens from entering the body and keeping fluids in, while sweat glands help regulate body temperature and prevent dehydration. Additionally, the skin produces oils and acids that can help kill harmful bacteria, further protecting against infection.

Question 17

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 18

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

Accepted Answer

Bone is a dynamic tissue made up of a mixture of hardened collagen (a protein) and minerals (like calcium and phosphate). This combination gives bone its strength and rigidity. Chondroitin sulphate is a component of cartilage, not bone. Columnar epithelial cells are found in tissues like the digestive tract and have no role in bone formation. Fibrous connective tissue is found in structures like tendons and ligaments, but not in bone.

Question 19

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 do not invest much energy in temperature regulation compared to endotherms, which require a lot of energy to maintain a constant internal temperature. This means that ectotherms can divert more energy towards other processes, such as survival during periods of food deprivation. In cool environments, an ectotherm's lower metabolic rate also means it will require less food to survive compared to an equally sized endotherm.

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

You have a cube of modelling 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?

An example of an ectothermic organism that has few or no behavioural 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?

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

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 ________.

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

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

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

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

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

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

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

Bone consists of ________.

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 ________.

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