Chapter 16 - Fill in the Blanks

Question 1

The _______ is a cone-shaped cavity in the front of the skull that contains the eyeball.

Answer 1

orbit

Question 2

The __________, another name for the openings through which blood vessels pass into the eye.

Answer 2

foramina

Question 3

The ______ ________ give passage to the optic nerve and the ophthalmic artery.

Answer 3

optic foramen

Question 4

_________ control the movement of the eye and also help maintain the shape of the eyeball.

Answer 4

muscles

Question 5

The ________ covers the eyeball and protects it from light, foreign particles, and impact. It also helps to keep the eyeball lubricated and free from dust and debris.

Answer 5

eyelids

Question 6

The ______ _______ includes the lacrimal gland, canaliculi sac, and nasolacrimal duct.

Answer 6

lacrimal apparatus

Question 7

The ______ ______ secretes tears through ducts onto he surface of the conjunctiva of the upper lid.

Answer 7

lacrimal gland

Question 8

The ______ _______ are two ducts at the inner corner of the eye that collect tears and drain into a sac.

Answer 8

lacrimal canaliculi

Question 9

Tears secreted bu the lacrimal glands are pulled into the ________ ___.

Answer 9

lacrimal sac

Question 10

The passageway draining lacrimal fluid into the nose is known as the ____________ ______.

Answer 10

nasolacrimal duct

Question 11

The eyeball contains 2 chambers. The _______ chamber is filled with a watery fluid known as ________ _____. And the ________ chamber is filled with a jellylike material called ________ _______.

Answer 11

(watery fluid) anterior = aqueous humor

(jellylike material) posterior = vitreous humor

Question 12

The eyeball’s outer layer is composed of the _______ or the white of the eye.

Answer 12

sclera

Question 13

The curved surface of the ________ is important because it bends light rays and helps to focus them on the surface of the retina.

Answer 13

cornea

Question 14

The _______ is the middle layer of the eyeball.

Answer 14

uvea

Question 15

The ______ is a coloured membrane in the eye.

Answer 15

iris

Question 16

The _______ has a circular opening in its center and is surrounded by muscles that contract or dilate to regulate the amount of light admitted into the eye.

Answer 16

pupil

Question 17

The ________ is the vascular membrane of the eye.

Answer 17

choroid

Question 18

The innermost layer of the eye is the _______ and contains photoreceptor cells.

Answer 18

retina

Question 19

There are 2 types of photoreceptor cells. The _____ are sensitive to dim light and used for night vision, and the _____ are sensitive to bright light and colour vision

Answer 19

rods (night vision)

cones (bright light / colour)

Question 20

The point at which nerve fibres from the retina converge to form the optic nerve is known as the _____ _____.

Answer 20

optic disk

Question 21

The _____ is suspended by ligaments just behind the iris. Contraction and relaxation of muscles control the ligaments to change the shape.

Answer 21

lens

Question 22

The function of the lens of the eye is to sharpen the focus of the light on the retina, this process is called ___________.

Answer 22

accommodation