Homeostasis ⚖️ℹ️

Question 1

homeostasis

Answer 1

ability to maintain relatively stable internal conditions even though the outside world changes continuously.

Question 2

What is the literal translation of homeostasis ? And what does it indicate?

Answer 2

static, or unchanging, it indicates a dynamic state of equilibrium

Question 3

Communication within the body is essential for homeostasis. Communication is accomplished chiefly by ?

Answer 3

the nervous and endocrine systems

Question 4

Communication is accomplished chiefly by the nervous and endocrine systems, which use ..

Answer 4

neural electrical impulses or bloodborne hormones, as information carriers.

Question 5

homeostatic control mechanisms are processes involving at least three components that work together.

Answer 5

• Receptor
• Control center
• Effector

Question 6

Receptor ?

Answer 6

*sensor that monitors the environment and responds to changes, called stimuli, by sending information (input) to the second component, the control center.

*Input flows from the receptor to the control center along the afferent pathway.

Question 7

Control center ?

Answer 7

*determines the set point, which is the level or range at which a variable is to be maintained. It *also analyzes the input it receives and *determines the appropriate response. Information (output) then flows from the control center to the third component, the effector, along the efferent pathway.

Question 8

Effector ?

Answer 8

provides the means for the control center’s response (output) to the stimulus. The results of the response then feed back to influence the effect of the stimulus, either reducing it so that the whole control process is shut off, or enhancing it so that the whole process continues at an even faster rate.

Question 9

Most homeostatic control mechanisms are ?

Answer 9

negative feedback mechanisms.

Question 10

negative feedback mechanisms.

Answer 10

the output shuts off the original effect of the stimulus or reduces its intensity. These mechanisms cause the variable to change in a direction opposite to that of the initial change, returning it to its “ideal” value.

Question 11

All negative feedback mechanisms have the same goal:

Answer 11

preventing severe changes within the body.

Question 12

positive feedback mechanisms

Answer 12

result or response enhances the original stimulus so that the response is accelerated. This feedback mechanism is “positive” because the change that results proceeds in the same direction as the initial change, causing the variable to deviate further and further from its original value or range.

Question 13

positive feedback mechanisms usually control ..

Answer 13

infrequent events that do not require continuous adjustments.

Question 14

positive feedback mechanisms are often referred to as ..

Answer 14

cascades. (from the Italian word meaning “to fall”).

Question 15

positive feedback mechanisms, may have only ..

Answer 15

local effects. For example, blood clotting is accelerated in injured vessels, but does not normally spread to the entire circulation.

Question 16

Why are the Positive feedback mechanisms rarely used to promote the moment-to-moment well-being of the body ?

Answer 16

Positive feedback mechanisms are likely to race out of control.

Question 17

Another important source of homeostatic imbalance occurs when ..

Answer 17

the usual negative feedback mechanisms are overwhelmed and destructive positive feedback mechanisms take over.

Some instances of heart failure reflect this phenomenon.

Question 18

As we age, our body’s control systems become ?

Answer 18

less efficient, and our internal environment becomes less and less stable

Question 19

the variable ..

Answer 19

the factor or event being regulated.