nervous communication

Question 1

how do animals as well as plants increase chances of survival

Answer 1

Animals increase their chances of survival by responding to changes in their external environment,
e.g. by avoiding harmful environments such as places that are too hot or too cold.

Question 2

what else do animals and plants respond to other than their external environment

Answer 2

They also respond to changes in their internal environment to make sure that the conditions
are always optimal for their metabolism (all the chemical reactions that go on inside them)

Question 3

what is a stimulus

Answer 3

Any change in the internal or external environment is called a stimulus.

Question 4

what do receptor cells detect

Answer 4

Receptors Detect Stimuli and Effectors Produce a Response

Question 5

what do receptor cells detect

Answer 5

Receptors detect stimuli — they can be cells or proteins on cell surface membranes.
There are loads of different types of receptors that detect different stimuli.

Question 6

what are effectors

Answer 6

Effectors are c ells that bring about a response to a stimulus, to produce an effect.
Effectors include muscle cells and cells found in glands, e.g. the pancreas.

Question 7

how do receptors communicate

Answer 7

Receptors communicate with effectors via the nervous system or the hormonal system, or sometimes using both.

Question 8

in what form does the nervous system send information

Answer 8

The Nervous System Sends Information as Electrical Impulses

Question 9

what is the nervous system made up of

Answer 9

The nervous system is made up of a complex network of cells called neurones. There are three main types

Question 10

what are the three main types of neurons

Answer 10

SENSORY NEURONS

transmit electrical impulses from receptors to the z Electrical impulses are also
central nervous system. (CNS) — the brain and spinal cord.

• MOTOR NEURONS

transmit electrical impulses from the CNS to effectors.

• RELAY NEURONES

transmit electrical impulses between sensory neurones and motor neurones.

Question 11

What is step 1 of the nervous system

Answer 11

A stimulus is detected by receptor cells and an electrical impulse is sent along a sensory neurone.

Question 12

What is step 2 of the nervous system

Answer 12

When an electrical impulse reaches the end of a neurone, chemicals called neurotransmitters
take the information across to the next neurone, which then sends an electrical impulse

Question 13

What is step 3 of the nervous system

Answer 13

The CNS (the coordinator) processes the information and sends impulses along motor neurones to an effector.

Question 14

what are the two systems the nervous system is split up into

Answer 14

the central nervous system and the peripheral nervous system

Question 15

what’s the central nervous system made up of

Answer 15

The central nervous
system (CNS) —
made up of the brain

Question 16

what’s the peripheral nervous system made up of

Answer 16

The peripheral nervous system —
made up of the neurones that connect
the C NS to the rest of the body.
It also has two different systems:

Question 17

what’s the somatic nervous system

Answer 17

The soma tic nervous
system controls conscious
activities, e.g. running
and playing video games

Question 18

what’s the automatic nervous system and what does it connect to

Answer 18

The autonomic nervous system
controls unconscious activities, e.g.
digestion. It’s got two divisions that
have opposite effects on the body: the parasympathetic nervous system and the sympathetic nervous system.

Question 19

what’s the parasympathetic nervous system

Answer 19

The parasympathetic nervous
system calms the body d own.
It’s the ‘rest and digest’ system.

Question 20

what’s the sympathetic nervous system

Answer 20

The sympathetic nervous system
gets the body ready for action.
It’s the ‘flight or fight’ system.