communication and homeostasis basics

Question 1

how do animals increase their chances of survival

Answer 1

By responding to changes in their external environment
(E.g. by avoiding places that are too hot or too cold)

• They also respond to changes in their internal environment to make sure that they have optimal conditions for their metabolism

Question 2

What is a change in internal or external environment called?

Answer 2

A stimulus

Question 3

what do receptors do

Answer 3

They detect stimuli

Question 4

What do effectors do

Answer 4

Cell that bring about a response to a stimulus to produce an effect

Question 5

What is cell signalling

Answer 5

When receptors communicate with effectors, and effectors communicate with other cells.

Question 6

Homeostasis definition

Answer 6

Control systems that keep your internal environment roughly constant.

• This is vital for for cells to function normally and stop them from being damaged

Question 7

Why is it important to maintain right concentration of glucose in the blood?

Answer 7

so there is always enough glucose available for respiration.

Question 8

what is negative feed back?

Answer 8

Mechanism that restores the level of something to normal level.

• However, if the change in levels is too big, then effectors may not be able to counteract this.

Question 9

What is positive feed back and why is it good

Answer 9

Positive feed back is when a change is amplified from the normal level.
- Effectors respond to further increase the level away from normal level

• useful when trying to rapidly activate something.
  ( e.g. blood clot after being injured)
• positive feed back aint involved with homeostasis because it does not keep your internal environment constant.