U5 B4 1HVTTO

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 1

B1 The nervous system

• Take off your jacket
  
• Put your things on your desk
  

       Book, notebook, pencil case

• Bag on the floor
  
• Read pages 110-114

Lesson goals

• You can describe the structure and functions of the nervous system
• You can describe the structure of nerve cells and nerves.
• You can describe a reflex arc

Today

• Recap
• The nervous system
• Cells of the nervous system
• Reflexes
  
• Time for hw
  
• End

At what moment do you become aware of a sound?

1. the moment sound enters your ear
2. the moment the sound reaches the eardrum
3. the moment the sound has reached the cochlea
4. The moment the impulse of the auditory nerve has reached the brain

In what part of the ear is the sound changed into an impulse?

1. ear drum
2. auditory ossicles
3. cochlea
4. auditory nerve

What part of the retina is best at seeing colours?

1. Sclera
2. Fovea
3. choroid
4. Blind spot

The pupil can change its size.
You're in your bed at night, you decide to turn on the lamp in your room, what happens?
The size of you pupil will change from .. to ..

1. Big to small
2. Small to big
3. Normal to big
4. It doesn't change

What part of the eye changes light stimuli into impulses?

1. Pupil
2. Lens
3. Retina
4. Optic nerve

Before you continue...

• Did you read the text on pages 110-114? 
• Yes? Great! Continue with the LessonUp
• No? Well... first read those pages! 

Nervous system

Central nervous system:

brain and spinal cord

You touch your bike, and you feel that it is very cold.
How does the impulse travel in your body?

1. skin > nerve > spinal cord > brain
2. brain > spinal cord > nerve > skin
3. skin > spinal cord > nerve > brain
4. skin > brain > spinal cord > nerve

You use your leg to kick a ball.
How does the impulse travel in your body?

1. muscle > nerve > spinal cord > brain
2. brain > spinal cord > nerve > muscle
3. brain > nerve > spinal cord > muscle
4. muscle > spinal cord > nerve > brain

senses take in stimuli from your environment

Making muscles move

Making glands produce substances

Nerve cell

• 1 nerve contains many nerve cells
• Axons take in impulses
• Axons send impulses away
• 3 types of nerve cell

S

M

I

Reflex arc

Conscious reaction = brain decides how to react 

                                            reaction is voluntary

Reflex = involuntary, fixed and fast reaction

                  to stimulus 

Suddenly a bright light is shining in your eyes, your pupils become smaller.

1. Reflex
2. Conscious reaction

Someone suddenly throws a small ball your way. Without too much trouble, you manage to catch the ball.

1. Reflex
2. Conscious reaction

You open the tap to wash your hands. The water is hot, you pull away your hands immediately.

1. Reflex
2. Conscious reaction

What you should do

• Do asgmt 1-3, 5, 7 pgs. 114-116

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zw = Working with whispering

• Teacher is available for questions (in London...)
• Only whisper with the student next to you
• Stay at your  desk