GOOD CARDS B1. 2.1 The Nervous system

Question 1

What does the nervous system enable us to do?

Answer 1

React to surroundings

Coordinate behaviours

Question 2

What is a receptor?

Answer 2

Cells

detect stimili (changes in environment)

Question 3

Identify different receptors and the stimuli they detect:

Answer 3

Receptors in eyes
sensitive to light

Ears
sound
changes in position –> enable us to keep our balance

On tougue, in nose:
chemicals
enable us taste + smell

Skin
touch
pressure 
pain
temperature changes

Question 4

What does light receptor cells consist of?

Answer 4

nucleus
cytoplasm
membrane
(like animal cells)

Question 5

What is a neurone?

Answer 5

Cells in nerves 
in which 
info from receptors 
passed along 
to brain

Question 6

What does the brain do after receiving impulses from receptors?

Answer 6

Coordinate the response

Question 7

Characteristics of reflex actions

Answer 7

Automatic + rapid

Question 8

What three neurones are involved in a reflex action?

Answer 8

Sensory, relay + motor neurone

Question 9

Describe what happens in a refle arc

Answer 9

1. Impulses from receptor
   pass along sensory neurone
   to central nervous system
2. At junction (synapse) sensory + relay in CNS
   a chemical released
   impulse sent along relay
3. chemical released
   synapse relay + motor in CNS
   impulse sent along motor
   to effector that brings abt response
4. Muscle: response by contracting
   Gland: response by releasing (secreting) chemical substances