Chapter 4: Homeostatic Control Mechanisms

Question 1

__________ - is the condition of equilibrium (balance) in the body’s internal environment due to the constant interaction of the body’s many regulatory processes.

Answer 1

Homeostasis

Question 2

The nervous system regulates homeostasis by sending electrical signals to organs that can counteract changes from the balanced state. This electrical signal is called:

Answer 2

nerve impulses

Question 3

____________ - includes many glands that secrete messenger molecules called hormones into the blood.

Answer 3

endocrine system

Question 4

State if True or False:

Nerve impulses typically cause rapid changes, but hormones usually work more slowly. Both means of regulation, however, work toward the same end, usually
through negative feedback systems.

Answer 4

True

Question 5

______________ - is a cycle of events in which the status of a body condition is monitored, evaluated, changed, remonitored, reevaluated, and so on.

Answer 5

feedback system or feedback loop

Question 6

Feedback Systems:

Each monitored variable, such as body temperature, blood pressure, or blood glucose level, is termed as ____________ . Any disruption that changes a controlled condition is called a _________ .

Answer 6

controlled condition

stimulus

Question 7

What are the three basic components of feedback system?

Answer 7

1. a receptor
2. a control center
3. an effector

Question 8

_________ - is a body structure that monitors changes in a controlled condition and sends input to a control center. This pathway is called an __________ .

Answer 8

receptor

afferent pathway

Question 9

___________ - sets the range of values within which a controlled condition should be maintained (set point), evaluates the input it receives from receptors, and generates output commands when they are
needed.

Answer 9

control center

Question 10

Output from the control center typically occurs as nerve impulses, or hormones or other chemical signals. This pathway is called an:

Answer 10

efferent pathway

Question 11

________ - is a body structure that receives output from the control center and produces a response or effect that
changes the controlled condition.

Answer 11

effector

Question 12

_______________ - reverses a change in a controlled condition.

Answer 12

negative feedback system

Question 13

___________ - pressure-sensitive nerve cells located in the walls of certain blood vessels, detect the higher pressure.

Answer 13

Baroreceptors

Question 14

______________ _ - tends to strengthen or reinforce a change in one of the body’s controlled conditions.

Answer 14

positive feedback system

Question 15

A particular component of a homeostatic control system recognizes slight changes in a variable and anticipates arrival of a potentially larger charge and thus, activates
appropriate systems to defend against the forthcoming change.

Answer 15

Feedforward system

Question 16

What are the three components of Hemostasis?

Answer 16

1. Negative feedback system
2. Positive feedback system
3. Feedforward system

Question 17

The following are examples of Negative Feedback. Except:

1. Temperature regulation
2. Blood pressure regulation
3. Thirst
4. Tachycardia

Answer 17

Except: 4

Question 18

_________ - A value at steady state that’s recognized and maintained by a homeostatic control process/ system/mechanism.

Answer 18

Set point

Question 19

_________ - The difference between the set point and the level of a (tightly) regulated variable.

Answer 19

Error signal

Question 20

Advantage of Error signal.

State if True or False:

If a constant error signal is present, we can have a constant response to it; therefore, regulate a persistent (constant) change.

Answer 20

True

Question 21

__________- Successful coping of an organism with presenting changes (environment); if not successfully adapt, equals death, therefore, it is survival of the fittest.

Answer 21

Adaptation

Question 22

___________ - Adaptive changes that occur in the body, in order to cope with prolonged exposure to a change, or an environmental stress.

Answer 22

Acclimatization