Vision (Slides 1-9, Quiz 3)

Question 1

What is glaucoma?

Answer 1

intraocular pressure is high

Question 2

What is poor accommodation?

Answer 2

unable to bend light and focus info onto the retina

Question 3

What is astigmatism?

Answer 3

eyes will change the direction of light over the photo receptors

Question 4

What is cataracts?

Answer 4

cloudy lens

Question 5

What are the 3 layers of the eye?

Answer 5

1) outer layer of the eyeball= sclera (the white of the eye)
2) middle layer= choroid
3) inner layer= retina (lines the back two-thirds of the eyeball)

Question 6

Which part of the eye is pigmented with melanin?

Answer 6

the iris

Question 7

Which part of the eye is a hole in the iris?

Answer 7

the pupil

Question 8

Suspensory ligaments are attached to what?

Answer 8

ciliary body and smooth muscle that is innervated by the ANS

Question 9

What is macular degeneration?

Answer 9

macula slowly degenerates and you wont be able to see with that part of the eye

Question 10

The receptors (photoreceptors- rods and cones) for vision are located where?

Answer 10

in the retina

Question 11

Which vitamin is required for rhodopsin (the protein found in photoreceptor disks that bind light)?

Answer 11

vit A

Question 12

How many different types of neurons are there in the eye?

Answer 12

5 types

Question 13

Which neurons in the retina send info away from the eye?

Answer 13

ganglion cells

Question 14

What is the first neuron in the visual pathway?

Answer 14

bipolar cells

Question 15

How many histo layers are there in the retina?

Answer 15

10 layers (light has to pass through all the layers, as photoreceptors are in the outer layer)

Question 16

Which layer of the retina houses the nucleus and cell bodies?

Answer 16

nuclear layer

Question 17

Which layer of the retina has synapses for axons?

Answer 17

plexiform layer

Question 18

Rods and cones have outer segments fills with discs containing….

test q

Answer 18

rhodopsin

Question 19

What is the pathway of light?

Answer 19

-light binds to photoreceptors
-this depolarizes and sends AP to bipolar cells
-bipolar cells send APs to ganglion cells
-ganglion cell axons project to the optic disc and out through the optic nerve CN II

Question 20

T/F: axons are unmyelinated in the retinal layers before the photoreceptors so that light can get through

Answer 20

true, then they are myelinated

Question 21

What is the blind spot of the eye and does not contain photoreceptors?

Answer 21

optic disc

Question 22

The _________ is a small depression in the retina of the eye where visual acuity is highest. The center of the field of vision is focused in this region because retinal cones are very concentrated here

Answer 22

fovea

Question 23

The ___________ is a larger area including and surrounding the fovea. This is the functional center of the retina

Answer 23

macula

Question 24

Which photoreceptors have a low threshold where very few photons (dim light) can depolarize it?

Answer 24

rods (rods only come with 1 type of rhodopsin whereas cones has several so the AP for rods is either on or off)

Question 25

Which photoreceptor requires bright light to be activated?

Answer 25

cones

Question 26

Long wave length of bright light would activate which cone?

Answer 26

red cone

Question 27

Middle wavelength of bright light would activate which cone?

Answer 27

green cones

Question 28

Short wavelength of bright light would activate which cone?

Answer 28

blue cone

Question 29

Which photoreceptor allows us to perceive color vision?

Answer 29

cones