11.1 Sensation Part 3

Question 1

What is the ciliary muscle?

Answer 1

muscle that varies the curvature of the lens and thus its refractive power

Question 2

What are the two photoreceptors?

Answer 2

rods
cones

Question 3

What are the bipolar cells of the eye?

Answer 3

neurons that have one axon and one dendrite

Question 4

What is the optic disk?

Answer 4

point on the retina where many axons form ganglion cells and converge to form the optic nerve

Question 5

What is the macula?

Answer 5

special region of the retina that contains the fovea centralis

Question 6

What is the fovea centralis?

Answer 6

part of the retina that contains only cones and is responsible for extreme visual acuity

Question 7

What is the protein in photoreceptors?

Answer 7

opsin

Question 8

What type of vision are rods responsible for and where are they located?

Answer 8

night vision; periphery of the retina

Question 9

What type of vision are cones responsible for and where are they located?

Answer 9

color vision and high acuity vision; fovea

Question 10

What is emmetropia?

Answer 10

normal vision

Question 11

What is myopia?

Answer 11

too much curvature of the lens resulting in light being focused in front of the retina; nearsightedness

Question 12

What is hyperopia?

Answer 12

too little curvature of the lens resulting in light being focused behind the retina; fairsightedness

Question 13

What is presbyopia?

Answer 13

inability to accommodate (focus)

Question 14

What is the optic chiasm?

Answer 14

where both optic nerves unite

Question 15

What is the optic tract?

Answer 15

optical axons once they pass by the optic chiasm