Homeostasis

Question 1

The tendency of a living body to maintain relatively stable internal conditions in spite of greater changes in its external environment is known as ______.

Answer 1

Homeostasis

Question 2

What is the term used for body conditions, such as temperature and blood pressure, that must remain within a narrow range and also can change?

Answer 2

Variable

Question 3

An individual is suffering from a fever of 102 degrees Fahrenheit. Ideal body temperature is 98.6 degrees Fahrenheit. The set point for body temperature is _____ degrees Fahrenheit

Answer 3

98.6

Question 4

Bodily changes are detected and responses are activated that reverse the change and restore stability and preserve normal body function during ______.

Answer 4

Negative feedback

Question 5

The organ that carries out a response that changes the value of the variable is called a(n) ______.

Answer 5

Effector

Question 6

Homeostasis is the body’s ability to maintain _____.

Answer 6

A relatively stable internal condition

Question 7

Identify the function of the control center within a feedback mechanism.

Answer 7

Receives and processes information

Question 8

Which of the following is/are characteristics of variables with regard to homeostasis?

Answer 8

1) They must remain within a narrow change.

2) Their values can change.

Question 9

Baroreceptors in the aorta detect an increase in blood pressure. Nerves send information to the brain. The brain compares the value of the blood pressure to a set point. Nerves send information to the heart. The heart beats slower. Blood pressure decreases. In this example the effector is the ______.

Answer 9

Heart

Question 10

In reference to living organisms, the set point can be defined as the _______.

Answer 10

ideal normal value of a condition such as blood pressure

Question 11

A structure, molecule or cell that detects a stimulus (or change in body variable) is called a(n)

Answer 11

Receptor

Question 12

Negative feedback is a mechanism that ______.

Answer 12

Reverses the change and maintains homeostasis

Question 13

If the body temperature rises, sweat glands produce sweat and the body cools. This is an example of ______ feedback.

Answer 13

Negative

Question 14

What portion of a feedback mechanism carries out a response to change a body variable?

Answer 14

Effector

Question 15

True or false: A deviation from a set point always results in disease.

Answer 15

False

Sometimes these deviations are beneficial, such as the changes in heart rate and blood pressure seen with exercise

Question 16

The part of the feedback mechanism that receives and processes information, relates it to other information, and makes a decision of action to be carried out by the effector is the ______.

Answer 16

Control center

Question 17

Blood pressure decreases below normal levels. Blood flow to the heart decreases. Heart is unable to pump as much blood. Blood pressure decreases even more. This is an example of _____ feedback.

Answer 17

Positive
(In positive feedback, the initial stimulus is reinforced. Here blood pressure decreases, something happens and blood pressure drops even more. This is an example of a harmful positive feedback mechanism).

Question 18

A sweat gland can adjust temperature when directed. A sweat gland is an example of a(n) ______.

Answer 18

Effector

Question 19

A feedback mechanism that represents a cycle where physiological change leads to an even greater change in the same direction is a ______.

Answer 19

Positive feedback

Question 20

In a feedback mechanism a stimulus is detected by a(n) ______.

Answer 20

Receptor

Question 21

Sweating in response to an increase in body temperature is part of a __ feedback mechanism to lower body temperature

Answer 21

Negative

Question 22

True or false: Positive feedback mechanisms are less common in healthy individuals than negative feedback mechanisms.

Answer 22

True

Positive feedback increases the deviation from homeostasis, and therefore, is rarely seen in health

Question 23

True or false: During some situations, there are beneficial deviations from body set points.

Answer 23

True

Sometimes deviations are beneficial, such as the changes in heart rate and blood pressure seen in exercise

Question 24

Body temperature decreases. Shivering occurs. Body temperature increases. This is an example of _____ feedback.

Answer 24

Negative
(In negative feedback, the response is opposite the original stimulus. Negative feedback maintains homeostasis. In this case there is a decrease in temperature and the body responds to increase temperature back to the normal range).

Question 25

In positive feedback, the response to the original stimulus ______.

Answer 25

Increases

Question 26

Positive feedback mechanisms are more commonly seen in ______ individuals.

Answer 26

Unhealthy