5.3 vision

• Biologie
• Middelbare school
• vwo
• Leerjaar 1

5.3 vision

First: Read par 5.3

then make this lesson up

The eye

Notes

• Eyebrow (wenkbrauw): Protects the eye against sweat and other liquids (vloeistoffen)

• Eyelashes (wimpers): protects the eye against dirt and bright light

• Sclera (harde oogvlies): white of the eye. The eye muscles are attached to the sclera

• Pupil: The pupil lets light into the eye.

Pupil reflex

Pupil gets smaller in bright light

Pupil gets larger in dim light

What do we
call this reflex?

1. Light reflex
2. Iris reflex
3. Pupil reflex
4. Light protection

When it is dark

1. The iris is large and the pupil is small
2. The iris is large and the pupil is large
3. The iris is small and the pupil is mall
4. The iris is large and the pupil is large

In bright light

1. circular muscles are contracted
2. circular muscels are relaxed
3. radia muscles are contracted
4. radial muscles are relaxed

Do this experiment toghether with you neighbour:
Keep both eyes open and place a hand before one of you eyes. Do this for 30 seconds. Then remove your hand. What happens with the pupil of your eyes. Explain your answer

https:

iris

retina

sclera

cornea

pupil

optic nerve

lens

retina

Cones are for: Color (red / blue / green)

Rods are for: Light (black / white)

retina

cones work well in bright light

rods function in dim light

the fovea is the most sensitive part (lots of cones)

Rods- Cones

Rods : Black and white/ unsharp image

Cones: colour/sharp 

fig 5.7 in book

retina

retina

blind spot/optic nerve

What part of the lens focuses the light rays

1. Lens
2. Pupil
3. Retina
4. Cornea

What is the biggest part of the eye

1. Rods
2. Lens
3. Vitreous body
4. Cornea

How do we see çolour

1. Rods
2. Cones
3. Lens
4. Cornea

Where can you find the highest amount of cones

1. Blind spot
2. Fovea
3. Optic nerve
4. Iris

In dim light the ...... are making an image.
What should be on the .....

1. Cones
2. Rods

Whe you use your rods the image is in .......

1. Black and white
2. Colour

When the image hits the retina, the image is upside down. What flips the image over so that it is right-side up

1. Lens
2. Retina
3. optic nerve
4. Brain

kidshealth.org

https:

Do experiments from your workbook

Exc 16

Exc 17

Exc 18

Exc 19

(-) minus lenses

(+) plus lenses

Short sighted: you can see clearly objects that are close by

Long sighted: you can see clearly objects far away

glasses

- short - sightedness: you can’t see sharp in the distance, you need - (concave) glasses, your eye is too long, or your lenze can’t flatten enough

- long - sightedness: you can’t see sharp up close, you need + (convex) glasses, your eye is too short, or your lenze can’t contract enough

Peter has problems reading his book, he only sees a blurred line. Peter has no problems looking in the distanceThis means that his lens is

1. to thick so the light is broken to much
2. to thick so the light is not broken to enough
3. to thin so the light is broken to much
4. to thin so the light is not broken to enough

This condition Peter has is called

1. short- sighted
2. long-sighted

Peter needs glasses with ......

1. A convex lens
2. A concave lens

When people get older they often have problems reading a book. They need glasses with a convex lens. Can you explain this

vocabulary?

read the paragraph 5.3 again and write down difficult words

or ask the teacher for assitance if you dont understand everything