Special Senses: the visual system

Question 1

• Lacrimal apparatus

Answer 1

o Lacrimal gland, lacrimal canaliculi, lacrimal sac, and nasolacrimal duct

Question 2

• Lacrimal glands

Answer 2

o Situated superior to the lateral aspect of the eye

o Release a dilute salt solution (tears)

Question 3

• Lacrimal puncta

Answer 3

o an opening through which fluid enters each lacrimal canaliculum.

Question 4

• Lacrimal canaliculi

Answer 4

o form the first part of the nasolacrimal drainage apparatus that drains tears produced by the lacrimal gland.

Question 5

• Nasolacrimal duct

Answer 5

o carries tears from the lacrimal sac into the nasal cavity.

Question 6

• Lysozyme

Answer 6

o Antibacterial enzyme

o Contained in lacrimal secretion

Question 7

• Eyelids/palpebrae

Answer 7

o Protect the anterior surface of each eye

Question 8

• medial commissure (canthus)/lateral commissure (canthus)

Answer 8

o form the lateral and medial corners of the eyes.

Question 9

• lateral caruncle

Answer 9

o fleshy raised area at the medial commissure

o produces whitish oily secretion

Question 10

• conjunctiva

Answer 10

o mucous membrane
o lines the internal surface of the eyelids and continues over the anterior surface of the eyeball to its junction with the corneal epithelium

Question 11

• ciliary glands

Answer 11

o modified sweat glands

o lie between the eyelash hair follicles and help lubricate the eyeball

Question 12

• tarsal glands

Answer 12

o are a special kind of sebaceous gland at the rim of the eyelids inside the tarsal plate

Question 13

• extrinsic eye muscles

Answer 13

o attached to the exterior surface of each eyeball
o control eye movement and make it possible for the eye to follow a moving object
o lateral rectus, medial rectus, superior rectus, inferior rectus, inferior oblique, superior oblique

Question 14

• fibrous layer

Answer 14

o protective layer composed of dense avascular connective tissue

Question 15

• cornea

Answer 15

o where light enters the eye

Question 16

• vascular layer

Answer 16

o called uvea

o middle layer of internal eye

Question 17

• choroid

Answer 17

o blood rich nutritive region containing a dark pigment that prevents light scattering within the eye

Question 18

• ciliary muscles

Answer 18

o smooth muscles important in controlling lens shaoe and ciliary processes

Question 19

• pupil

Answer 19

o a rounded open which lets light pass

Question 20

• intrinsic muscles of the eye

Answer 20

o spincter pupillae of iris
o dilator pupillae of iris
o ciliary muscles

Question 21

• retina

Answer 21

o innermost sensory layer of the eye

o three layer: photoreceptors, bipolar cells, and ganglion cells

Question 22

• pigmented layer

Answer 22

o abuts the choroid and extends anteriorly to cover the ciliary body and the posterior side of the iris

Question 23

• neural layer

Answer 23

o extends anteriorly only to the ciliary body

o contains the photoreceptors (cones and rods)

Question 24

• optic disc/blind spot

Answer 24

o where the optic nerve leaves the eyeball

o located in a weak spot in the fundus(posterior wall)

Question 25

• macula lutea/yellow spot

Answer 25

o an area of high cone density

Question 26

• fovea centralis

Answer 26

o a tiny pit about 0.4 mm in diameter

o contains only cones and is in the area of greatest visual acuity

Question 27

• lens

Answer 27

o a flexible crystalline structure held vertically the in eyes interior by the ciliary zonule attached to the ciliary body

Question 28

• ciliary zonule

Answer 28

o suspensory ligament

Question 29

• scleral venous sinus

Answer 29

o reabsorbs aqueous humor

Question 30

• optic nerve

Answer 30

o bundle of fibers where axons of the ganglion cells leave the retina

Question 31

• sclera

Answer 31

o White of the eye

o Forms bulk of the fibrous layer

Question 32

• conjunctivitis

Answer 32

o inflammation of the conjunctiva often accompanied by redness of the eye

Question 33

• sty

Answer 33

o an inflammation of one of the ciliary glands or small oil gland

Question 34

• cataracts

Answer 34

o cause vision to become hazy or entirely obstructed

Question 35

• glaucoma

Answer 35

o when intraocular pressure reaches dangerously high levels the retina and optic nerve are compressed resulting in pain and possible blindness