3.2 Seeing

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

Chapter 3: Observing

3.2 Seeing

Schedule today

Welcome

Learning objectives

Check knowledge 3.1

Check knowledge 3.2 (the eye)

Instruction

Homework

End of class

Learning objectives

You will learn 

- how your eyes are constructed

- how you are able to see colours

- how you control the amount of light in your eyes

- how your eyes are able to focus 

- how you see depth.

Translate:
Prikkel

1. Sense
2. Stimuli
3. Impulse
4. Neuron

Translate:
Sense

1. Reageren
2. Ruiken
3. Zintuig
4. Prikkel

Wat is a sensory organ?

1. A change in the environment
2. Electrical signals that travel through the nerves to the brain
3. An organ that can sense stimuli and convert them into impulses
4. The processing of impulses from the environment

What is a stimulus?

1. Something you feel when you touch a sharp object.
2. Information from your surroundings.
3. A signal that's being transported through the body.
4. A part of the central nervous system.

A stimulus can be picked up by a sensory organ. Then it is being converted into an impulse. What is an impulse?

1. A chemical reaction of the body.
2. An electrical signal.
3. The same as a stimulus.

What are senses of heat?

1. Senses that are hot.
2. Senses that get hot when you use them.
3. Senses that percieve heat.
4. Senses that only operate during the summer.

Check knowledge 3.2

Do you already know all the parts of the eye?

eyelid

tearduct

tear gland

eyebrow

eyelash

Eyebrow

Eyelashes

Tear fluid

Eyelid

sweat and other moisture runs past your eyes and not in them

protects against dirt and excessively bright light

protects against dehydration and cleans the eye

can close as a protective layer over your eye 

Lens

Iris

Cornea

Eye muscle

Choroid

Retina

Fovea

Blind spot

Optic nerve

Sclera

Vitreous body

The outside of the eyes

Rods and cones

Rods (Staafjes): Black, white, grey

- work during nighttime

Cones (Kegeltjes): colours

- work during daytime

- Three types: Red, green, blue  

Pupillary reflex (pupilreflex)

= enlarging the pupils in dim light and making the pupils smaller in bright light.

Accomodating (accomoderen)

Accomodating = Making the eye lens more convex (bol) or flat (plat).

Ciliary muscle (straallichaam)=  A muscle surrounding the eye lens.

Lens is attached to suspensory ligaments (lensbandjes).

Glasses

accomodating or eyeball length 

Far sighted (Verziend): Short eyeball, only clear vision of distant objects.

Short-sighted (Bijziend): Long eyeball, only clear vision of nearby objects. 

What?	check homework Finish 3.2! --> This is homework! 12, 13, 16-18, 20, 23, 24, 28
How?	In your workbook. Use the information from your textbook.
Help?	You may gently consult with your neighbor. Raise your hand if the two of you can't figure it out.
Time?	15 minutes
Finished?	Study the PIF or write a summary of 3.2.
Product	You have practiced 3.2!