The Special Senses (Vision Part 2)

Question 1

A long eyeball causes the image to focus in the front of the retina and not on it (nearsightedness)

Answer 1

Myopia

Question 2

A short eyeball or “lazy lens” causes the image to focus behind the retina instead of on it (farsightedness)

Answer 2

Hyperopia

Question 3

Visual Receptors of the eye

Answer 3

Rods and Cones

Question 4

responds to limited amounts of light

Answer 4

Rods

Question 5

Black and white vision
100 times more sensitive than the other
nerve fibers converge

Answer 5

Rods

Question 6

Respond to greater amounts of light

Answer 6

Cones

Question 7

Color Vision

Provides a sharp image because nerve fibers don’t converge

Answer 7

Cones

Question 8

Spot, close to the blind spot, where the light focuses

Answer 8

Fovea Centralis

Question 9

What is special about the fovea centralis

Answer 9

has all cones with no converging nerves, so it provides the sharpest image

Question 10

What is the pigment in rods; “visual purple”

Answer 10

rhodopsin

Question 11

When rhodopsin is exposed to light, it decomposes into

Answer 11

Opsin and retinol

Question 12

Enzyme that begins a chain reaction which hyperpolarizes the receptor cell which, in turn, causes an action potential in retinal neurons

Answer 12

Opsin

Question 13

what does opsin have to do to cause an action potential in retinal neurons

Answer 13

it begins a chain reaction which hyperpolarizes the receptor cell

Question 14

compound synthesized from vitamin A

Answer 14

Retinol

Question 15

Night blindness which is usually dues to insufficient Vitamin A, limiting rhodopsin production and leads to rod degeneration

Answer 15

Nyctalopia

Question 16

What is due to pigments made from retinal and different opsins

Answer 16

Color Vision

Question 17

What are the different type of cones that respond to different wavelengths of light

Answer 17

Erythrolabe
Chlorolabe
Cyanolabe

Question 18

What is erythrolabe most sensitive to (erythrocyte= blood cells)

Answer 18

sensitive to red light waves

Question 19

What is chlorolabe most sensitive to

Answer 19

sensitive to green light waves

Question 20

What is Cyanolabe most sensitive to

Answer 20

sensitive to blue light waves

Question 21

Congenital lack of one or more cone types, travels on X chromosomes

Answer 21

Color Blindness

Question 22

Seeing with two eyes

Answer 22

Stereoscopic vision

Question 23

What allows perception of distance and depth, as well as height and width of objects

Answer 23

Stereoscopic Vision

Question 24

The perception of depth is due to

Answer 24

the differences in the images from the two eyes

Question 25

How do yo actually see, in other words what is the path that a visual impulse takes

Answer 25

Retina-> optic nerve -> optic chiasma

some cross optic chiasma-> thalamus-> visual cortex of cerebrum

Other impulses pass into brain stem and function in various visual reflexes