Homeostasis And Nervous System

Question 1

What is homeostasis

Answer 1

Regulation of internal conditions of a cell/ organism in response to internal and external changes

Question 2

Why is homeostasis important

Answer 2

Keeps conditions constant for enzyme action and cell functions

Question 3

Homeostasis includes control of:

Answer 3

• blood glucose concentration
• body temp
• water and ion levels

Question 4

The control systems may involve:

Answer 4

• responses using nerves

- chemical responses using hormones

Question 5

All control systems include:

Answer 5

• receptors (detect stimuli- changes in environment)
• coordination centres (brain spinal cold etc) which receive and process info from receptors
• effectors (muscles or glands) which bring about responses that restore optimum levels

Question 6

What is negative feedback

Answer 6

• receptor detects change in a stimulus
• coordinating centre compares stimulus to a set point
• effector then produces a response to correct any difference from set point

Question 7

Reflex actions are automatic and rapid so they can protect the body. They do not involve the conscious part of brain:

Answer 7

1) pain stimulus is detected by receptors
2) impulses from receptor pass along a sensory neurone to CNS
3) an impulse then passes through a relay neurone
4) effector (usually a muscle) response

Question 8

Meaning of negative feedback

Answer 8

-responds when conditions change from the set point and returns conditions to this set point