1B3
Sensory System
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1B3 Sensory System
OB30
locate the main parts
of the eye on a model or diagram
and describe the function of the
cornea, iris, lens, pupil, retina,
optic nerve and ciliary muscle
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
front view of the eye
“white”
pupil
iris
click for labels
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
Inside of the eye
cornea
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
can you
remember
what’s
what?
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G
CLICK FOR
ANSWERS
A
CORNEA
B
RETINA
C
PUPIL
D
OPTIC NERVE
E
IRIS
F
LENS
G
CILIARY MUSCLE
OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
the cornea allows light
to enter the eye, and
refracts (bends) the rays
light rays
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
the iris contracts and relaxes in
response to light conditions…
…this changes the size of the
pupil, controlling the amount of
light entering the eye…
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OB30 locate the main parts of the eye on a model or
diagram and describe the function of the cornea, iris,
lens, pupil, retina, optic nerve and ciliary muscle
the lens focuses light rays to form a clear image on the
retina, where sensory cells detect the image
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
the optic nerve
brings a message
to the brain about
what we see
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
front view
lens
ciliary muscle
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side view
l
e
n
s
the function
of the ciliary
muscle is to
contract and
relax to
change the
shape of the
lens
OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
Choose a name from the list above to match the functions in the table
1. contains sensory cells which detect images
retina
2. contracts and relaxes to change the shape of the lens
ciliary muscle
3. allows light into the eye and refracts (bends) the rays
cornea
4. brings messages to brain about what we are seeing
optic nerve
5. allows light into the inside of the eye
pupil
6. contracts and relaxes to change the size of the pupil
iris
7. focuses a clear image on the retina
lens
click for answers
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OB30 locate the main parts of the eye on a model or diagram and
describe the function of the cornea, iris, lens, pupil, retina, optic
nerve and ciliary muscle
Look at the
diagram
and explain
what is
happening
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What do you think?
1. Why do we need to blink?
2. Find out what happens to the size of the
pupil of your eye (i) in bright light (ii) in
dim light ?
3. The eye is round, but the cornea at the
front is extra curved. Can you think of a
reason for this?
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1B3
Sensory System
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