Special sense- 2

Question 1

spherical, fluid-filled structure enclosed by three layers

Answer 1

eye

Question 2

Layers of the eye

Answer 2

From outermost to innermost, these are:
The sclera/cornea
The choroid/ciliary body/iris
The retina

Question 3

Question 4

What happens to the pupil in bright light

Answer 4

• Parasympathetic stimulation

- Circular muscles cause pupillary constriction

Question 5

What happens to the pupil in dim light

Answer 5

• Sympathetic stimulation

- Radial muscles cause pupillary dilation

Question 6

light rays focus on

Answer 6

retina

Question 7

Rods and Cones

Answer 7

Photoreceptors

Question 8

True of False

The retina contains 20 times more rods than cones

Answer 8

True

Question 9

High Sensitivity

Answer 9

Rods

Question 10

Lower Sensitivity

Answer 10

Cones

Question 11

Cone Vision Has ______ Acuity; Rod Vision Has ______ Acuity

Answer 11

High

Low

Question 12

Provide Colour Vision

Answer 12

Cones

Question 13

Provide Vision in Shades of Gray

Answer 13

Rods

Question 14

There are ____ different photopigments, one in the _______ and ___________
—red, green, and blue cones.

Answer 14

Four
rods
one in each of three types of cones

Question 15

Anterior cavity

clear watery fluid-filled that is continually formed and carries nutrients to the cornea and lens

Answer 15

Aqueous humor

Question 16

Middle layer of nerve cells in the retina, important in retinal processing of light stimuli

Answer 16

Bipolar cells

Question 17

Route of passage of the optic nerve and blood vessels

Answer 17

Blind spot

Question 18

Middle layer of the eye

Pigmented to prevent scattering of light rays in the eye; contains blood vessels that nourish the retina

Answer 18

Choroid

Question 19

Specialized anterior derivative of the choroid layer, forms a ring around the outer edge of the lens, produces aqueous humor and contains the ciliary muscle

Answer 19

Ciliary body

Question 20

Circular muscular component of the ciliary body; attached to the lens via suspensory ligaments
- Important in accommodation

Answer 20

Ciliary muscle

Question 21

Anterior, clear, outermost layer of the eye

Contributes most extensively to eyes refractive ability

Answer 21

Cornea

Question 22

exact center of the retina, region with the greatest aquity

Answer 22

Fovea

Question 23

Inner layer of nerve cells in the retina, important in retinal processing of light stimulus; form the optic nerve

Answer 23

Ganglion cells

Question 24

Visible pigmented ring of muscle within the aqueous humor; varies size of the pupil by variable contraction, responsible for eye colour

Answer 24

Iris

Question 25

Between the aqueous humor and vitreous humour; attaches to the ciliary muscle by suspensory ligaments
Provides variable refractive ability during accommodation

Answer 25

Lens

Question 26

Area immediately surrounding the fovea

Answer 26

Macula lutea

Question 27

First part of the visual pathway to the brain, leaves each eye at the optic disk (blind spot)

Answer 27

Optic nerve

Question 28

Permits variable amount of light to enter the eye, anterior round opening in the middle of the iris

Answer 28

Pupil

Question 29

Innermost layer of the eye, contains the photoreceptors ( rods and cones)

Answer 29

Retina

Question 30

Tough outer layer of the eye, protective connective tissue coat; forms the visible white part of the eye

Answer 30

Sclera

Question 31

Important in accommodation, suspended between ciliary muscle and lens

Answer 31

Suspensory ligaments

Question 32

between the lens and retina

Semiliquid, jellylike substance that helps maintain spherical shape of the eye

Answer 32

Vitreous humor