Feedback systems (Ch 1)

Question 1

Most homeostatic control mechanisms are

Answer 1

negative feedback mechanisms

Question 2

Negative feedback causes the variable to change in a direction

Answer 2

opposite to the original change

Question 3

When the variable goes in the opposite direction

Answer 3

the “ideal” value is achieved.

Question 4

In negative feedback, the output or response shuts off the

Answer 4

original stimulus or reduces its intensity.

Question 5

What doe the nervous system control

Answer 5

Regulating body temp, withdrawal reflex

Question 6

Regulating body temp is controlled by what part of the brain

Answer 6

hypothalamus

Question 7

what does the Endocrine System controls

Answer 7

Blood glucose levels (pancreatic hormones)

Question 8

To carry out normal metabolism, body cells need to have a constant supply of

Answer 8

glucose

Question 9

the major source for producing energy (ATP)

Answer 9

glucose

Question 10

in the endocrine system, in normal metabolism, the stimulus is the rising

Answer 10

blood glucose level (too much sugar)

Question 11

In the endocrine system, the increase in sugar levels stimulate the

Answer 11

insulin-producing cells of the pancreas – (receptor).

Question 12

known as the control center in the endocrine system

Answer 12

pancreas

Question 13

Where do the pancreas release insulin

Answer 13

into the blood

Question 14

The pancreas releasing insulin into the blood does what

Answer 14

speeds up the uptake of glucose by most of the body cells

Question 15

The pancreas also encourages the liver and muscles to

Answer 15

store excess glucose and glycogen – effector so that there is a reserve supply when needed

Question 16

What is the goal of all negative feedback mechanisms

Answer 16

to prevent severe changes within the body

Question 17

Other areas controlled via negative feedback

Answer 17

Heart rate
Blood pressure
Rate and depth of breathing
Blood oxygen levels
Carbon dioxide levels
Minerals

Question 18

Control infrequent events that don’t require continuous adjustments

Answer 18

Positive feedback

Question 19

Enhances the original stimulus so the activity (output) is accelerated

Answer 19

Positive feedback

Question 20

Why is positive feedback positive

Answer 20

the change that occurs is in the same direction as the initial disturbance

Question 21

Once initiated, there is a series of events which sort of lead to what kind of affect

Answer 21

Waterfall

Question 22

Positive feedback is also referred to as

Answer 22

Cascades

Question 23

Two main areas of positive feedback are

Answer 23

enhancement of labor contractions

blood clotting

Question 24

Most disease is thought to be a result of what kind of disturbance

Answer 24

homeostatic; homeostatic imbalance

Question 25

Can also occur when the normal negative feedback mechanisms are overwhelmed and destructive positive feedback mechanisms take over

Answer 25

Homeostatic Imbalance