4.5 Homeostasis and NS structure and function Flashcards Preview

11B1 - AQA Biology Trilogy > 4.5 Homeostasis and NS structure and function > Flashcards

Flashcards in 4.5 Homeostasis and NS structure and function Deck (20)
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1

Homeostasis is...

The maintenance of a constant internal environment

2

Name 4 internal conditions that need to be controlled?

water and ions
temperature
glucose
waste

3

What 2 control systems do we have in our body to regulate your internal environment?

nervous and hormonal

4

Your control systems have what 3 main components which work together to maintain a steady condition. Name them

-receptors
-coordination centres - brain/spinal cord/pancreas
-effectors

5

what are receptors?

special cells that detect stimuli and then send an electrical message along the sensory neurone to the CNS

6

Stimuli are..

changes in the environment (that are detected by receptors)

7

An effector is..

a muscle or gland that brings about a response

8

Where do sensory neurones carry electrical impulses from and to?

From receptors to the CNS

9

Where do motor neurones carry electrical impulses from and to?

From the CNS to the effector (muscle or gland)

10

What is a relay neurone?

A short neurone that carries an electrical impulse around the CNS in a reflex action

11

Where do you find a synapse?

The small gap between the axon of one nerve and the dendrites of another

12

Which type of chemical moves across a synapse

Neurotransmitter

13

What is a reflex response

an automatic response that you do not have to think about (involuntary)

14

How many neurones make up an reflex arc?

Three

15

Why are reflex actions beneficial?

Prevent us from harm. Do not have to be learned.

16

Name 4 stimuli that can be detected by receptors in the skin

Touch, pressure, temp, pain

17

How do neurotransmitters travel across a synapse

by diffusion

18

What comes next?

stimulus --> receptor--> ?

Sensory neurone

19

What comes next?

CNS (co-ordinator)---> motor neurone ---> ?

Effector

20

Where can receptors be found? (5)

Eyes, ears, tongue, nose, skin