Topic 9.7 Eye

Question 1

What is the fovea?

Answer 1

Spot on retina
Where highest number of come cells found

Question 2

What type of cells are rod and cone cells?

Answer 2

Receptor cells

Question 3

Why is the optic nerve the blind spot?

Answer 3

No receptor cells there

Question 4

What are the pair of antagonistic muscles in the eye?

Answer 4

Ciliary muscles
And
Suspensory ligaments

Question 5

What do both cone and rod cells have in common?

Answer 5

• on retina
• are receptor cells
• contain pigments (in disks)(in outer segment of rod and cone cells)
• inner segment has many mitochondria
• both share synapse with bipolar cells

Question 6

What are the differences between rod and cone cells?

Answer 6

Rod / cone
Not / colour sensitive
Dim light sensitive / not
More in retina / less
Contain rhodopsin / iodopsin
Can spatial summation w bipolar cell / only 1:1

Question 7

Why does cone cells have high visual acuity but not rod cells?

Answer 7

Cone cells have 1:1 ratio with bipolar cell, so higher resolution
Rod cells can spatially summate to converge to bipolar cells so resolution is lower

Question 8

What is the direction of travel of light and action potential?

Answer 8

Opposite to each other
Light towards the back of retina
Action pot from back of retina

Question 9

Retinal in rhodopsin is a ___ isomer.
Retinal on its own is a ___ isomer.

Answer 9

cis
trans