What Do You Know About Human Body Temperature? Quiz

1. The body's automatic tendency to maintain a constant internal environment is termed

Balanced equilibrium.

Physiological chance.

Homeostasis.

Static equilibrium.

Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes. It involves various physiological processes that help regulate temperature, pH levels, blood pressure, and other vital parameters within a narrow range. This ensures optimal functioning of cells, tissues, and organs. The term "balanced equilibrium" is not commonly used in biology or physiology, "physiological chance" does not accurately describe the concept, and "static equilibrium" refers to a state of balance without any change, which is not applicable to the body's internal environment. Therefore, the correct answer is homeostasis.

Explanation

Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes. It involves various physiological processes that help regulate temperature, pH levels, blood pressure, and other vital parameters within a narrow range. This ensures optimal functioning of cells, tissues, and organs. The term "balanced equilibrium" is not commonly used in biology or physiology, "physiological chance" does not accurately describe the concept, and "static equilibrium" refers to a state of balance without any change, which is not applicable to the body's internal environment. Therefore, the correct answer is homeostasis.

2. An overheated and sick dog has an impaired thermoregulatory response if it

Increases its evaporative heat loss.

Decreases its metabolic heat production.

Increases its body temperature to match the environmental temperature.

Increases its vasodilation in blood vessels near the skin.

When a dog is overheated and sick, its thermoregulatory response is impaired, meaning it is not able to regulate its body temperature effectively. In order to try to cool down, the dog may increase its evaporative heat loss, such as by panting or sweating. However, this does not mean that the dog is able to match its body temperature to the environmental temperature. In fact, increasing its body temperature to match the environmental temperature would be counterproductive and would not help the dog cool down.

Explanation

When a dog is overheated and sick, its thermoregulatory response is impaired, meaning it is not able to regulate its body temperature effectively. In order to try to cool down, the dog may increase its evaporative heat loss, such as by panting or sweating. However, this does not mean that the dog is able to match its body temperature to the environmental temperature. In fact, increasing its body temperature to match the environmental temperature would be counterproductive and would not help the dog cool down.

3. Positive feedback has occurred when

An increase in blood sugar increases the secretion of a hormone that stores sugar as glycogen.

A decrease in blood sugar increases the secretion of a hormone that converts glycogen to glucose.

A nursing infant's sucking increases the secretion of a milk-releasing hormone in the mother.

An increase in calcium concentration increases the secretion of a hormone that stores calcium in bone.

When a nursing infant sucks, it stimulates the release of a hormone in the mother that triggers the production and release of milk. This is a positive feedback mechanism because the action of the infant sucking leads to an increase in the secretion of the hormone, which in turn leads to more milk production.

Explanation

When a nursing infant sucks, it stimulates the release of a hormone in the mother that triggers the production and release of milk. This is a positive feedback mechanism because the action of the infant sucking leads to an increase in the secretion of the hormone, which in turn leads to more milk production.

4. In mammals this response is known as fever, but it is known to raise body temperature in other bacterially infected animals, including lizards, fishes, and cockroaches:

Growth of hair

Reduced metabolic rate

Sweating

A change in thermostat "set-point"

When animals are infected with bacteria, including mammals, lizards, fishes, and cockroaches, their body temperature increases as a response known as fever. This increase in body temperature is regulated by the thermostat "set-point" in the body, which is responsible for maintaining the normal body temperature. In the case of bacterial infection, the thermostat "set-point" is changed, causing the body temperature to rise. This change in the thermostat "set-point" is the correct answer.

Explanation

When animals are infected with bacteria, including mammals, lizards, fishes, and cockroaches, their body temperature increases as a response known as fever. This increase in body temperature is regulated by the thermostat "set-point" in the body, which is responsible for maintaining the normal body temperature. In the case of bacterial infection, the thermostat "set-point" is changed, causing the body temperature to rise. This change in the thermostat "set-point" is the correct answer.

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

The core body temperature of a runner rises gradually from 37°C to 45°C.

The kidneys excrete salt into the urine when dietary salt levels rise.

A blood cell shrinks when placed in a solution of salt and water.

The blood pressure increases in response to an increase in blood volume.

This answer is correct because it describes a homeostatic control system where the kidneys regulate the levels of salt in the body. When dietary salt levels rise, the kidneys detect this change and excrete the excess salt into the urine to maintain a stable salt balance in the body. This process helps to maintain homeostasis by regulating the concentration of salt in the body fluids.

Explanation

This answer is correct because it describes a homeostatic control system where the kidneys regulate the levels of salt in the body. When dietary salt levels rise, the kidneys detect this change and excrete the excess salt into the urine to maintain a stable salt balance in the body. This process helps to maintain homeostasis by regulating the concentration of salt in the body fluids.