Eyes And Ears

Question 1

3 layers of the eye

Answer 1

Fibrous layer
Vascular layer
Retina

Question 2

Bathes the iris and the lens and fill the anterior chamber between the cornea and iris and the posterior chamber between the iris and lens

Answer 2

AQUEOUS HUMOR

Question 3

Lies behind the lens and its zonular fibers and contains a large gelatinous mass of transparent connective tissue called the vitreous body.

Answer 3

VITREOUS CHAMBER

Question 4

The posterior vitreous chamber, surrounded by the retina, lies behind the lens and its zonular fibers and contains a large gelatinous mass of transparent connective tissue called the _________.

Answer 4

VITREOUS BODY

Question 5

The ________ layer, external layer of the eyeball protects the more delicate internal structures and provides sites for muscle insertion.

Answer 5

FIBROUS

Question 6

The white posterior five-sixths of the fibrous layer of the eye

Answer 6

SCLERA

Question 7

Collagen type of sclera

Answer 7

TYPE I

Question 8

Muscles that moves the eye and inserts into the anterior region of the sclera

Answer 8

EXTRAOCULAR MUSCLE

Question 9

Posteriorly the sclera thickens to approximately 1 mm and joins with the epineurium covering the optic nerve. Where it surrounds the choroid, the sclera includes an inner ___________.

Answer 9

SUPRACHOROID LAMINA

Question 10

Anterior one-sixth of the eye

Answer 10

CORNEA

Question 11

Epithelium of cornea

Answer 11

NON-KERATINIZED STRATIFIED SQUAMOUS EPITHELIUM

Question 12

True or False: The BASAL CELLS have a high proliferative capacity important for renewal and repair of the corneal surface

Answer 12

TRUE

Question 13

Basal cells of the corneal surface emerge from stem cells in the ________ that encircles the cornea.

Answer 13

CORNEOSCLERAL LIMBUS

Question 14

True or False: Corneal epithelium also has one of the richest sensory nerve supplies of any tissue.

Answer 14

TRUE

Question 15

Contributes to the stability and strength of the cornea, helping to protect against infection of the underlying stroma.

Answer 15

BOWMAN MEMBRANE

Question 16

Also known as SUBSTANTIA PROPRIA and makes up 90% of the cornea’s thickness.

Answer 16

STROMA

Question 17

Stroma consists of approximately 60 layers of (PARALLEL OR PERPENDICULAR) collagen bundles aligned at approximately right angles to each other and extending almost the full diameter of the cornea.

Answer 17

PARALLEL

Question 18

This contributes to the transparency of the stroma of the cornea.

Answer 18

The uniform orthogonal array of collagen fibrils

Question 19

Located between the collagen lamellae are cytoplasmic extensions of flattened fibroblast-like cells called _____.

Answer 19

KERATOCYTES

Question 20

Help maintain the precise organization and spacing of the collagen fibrils.

Answer 20

Ground substance which contains proteoglycans such as lumican, with keratan sulfate and chondroitin sulfate

Question 21

Corneal layer located posteriorly of the stroma which supports the internal simple squamous corneal endothelium

Answer 21

DESCEMET’S MEMBRANE

Question 22

Largely responsible for regulating the proper hydration state of the corneal stroma to provide maximal transparency and optimal light refraction.

Answer 22

Na+/K+ ATPase pumps in the basolateral membranes

Question 23

Encircles the cornea. Transitional area where the transparent cornea merges with the opaque sclera.

Answer 23

LIMBUS

Question 24

At the limbus, Bowman membrane ends and the surface epithelium becomes more stratified as the ________ that covers the anterior part of the sclera (and lines the eyelids)

Answer 24

CONJUNCTIVA

Question 25

True or False: Epithelial stem cells located at the limbus surface give rise to rapidly dividing progenitor cells that move centripetally into the corneal epithelium.

Answer 25

TRUE

Question 26

At the limbus Descemet᾿s membrane and its simple endothelium are replaced with a system of irregular endothelium-lined channels called the _______.

Answer 26

TRABECULAR MESHWORK

Question 27

Trabecular meshwork penetrates the stroma at the corneoscleral junction and allow slow, continuous drainage of aqueous humor from the anterior chamber. This fluid moves from these channels into the adjacent larger space of the _________.

Answer 27

Canal of Schlemm

Question 28

Three parts of the uvea

Answer 28

CHOROID CILIARY BODY IRIS

Question 29

Located in the posterior two-thirds of the eye, the choroid consists of loose, well-vascularized connective tissue and contains numerous melanocytes.

Answer 29

CHOROID

Question 30

This inner part of the choroid has a rich microvasculature important for nutrition of the outer retinal layers.

Answer 30

choroidocapillary lamina

Question 31

Thin extracellular sheet, is composed of collagen and elastic fibers surrounding the adjacent microvasculature and basal lamina of the retina’s pigmented layer.

Answer 31

BRUCH MEMBRANE

Question 32

The anterior expansion of the uvea that encircles the lens, lies posterior to the limbus

Answer 32

Ciliary body

Question 33

Contraction of these muscles affects the shape of the lens and is important in visual accommodation

Answer 33

Ciliary muscle

Question 34

Epithelium of ciliary process

Answer 34

Low columnar epithelium / ciliary epithelium

Question 35

Aqueous humor is secreted by _________ into the _______ chamber, flows through the pupil into the________ chamber, and drains at the angle formed by the cornea and the iris into the channels of the trabecular meshwork and the scleral venous sinus, from which it enters venules of the sclera.

Answer 35

Ciliary process Posterior anterior

Question 36

Ciliary zonule is composed of

Answer 36

Fibrillin-1 and 2

Question 37

The most anterior extension of the middle uveal layer which covers part of the lens, leaving a round central pupil .

Answer 37

Iris

Question 38

The anterior surface of the iris, exposed to aqueous humor in the anterior chamber, consists of a dense layer of with interdigitating processes and is unusual for its lack of an epithelial covering

Answer 38

fibroblasts and melanocytes

Question 39

True or False: T he posterior surface of the iris has a three-layered epithelium continuous with that covering the ciliary processes, but very heavily filled with melanin.

Answer 39

False, two-layered epithelium

Question 40

True or False: The highly pigmented anterior epithelium of the iris blocks all light from entering the eye except that passing through the pupil.

Answer 40

False, posterior

Question 41

Myoepithelial cells form a partially pigmented epithelial layer and extend contractile processes radially as the very thin _________ muscle.

Answer 41

Dilator pupillae

Question 42

Smooth muscle fibers form a circular bundle near the pupil as the _________ muscle

Answer 42

sphincter pupillae

Question 43

Parasympathetic or Sympathetic Dilator pupillae muscle: Sphincter pupillae muscle:

Answer 43

Sympathetic- dilates the pupil | Parasympathetic- constricts the pupil

Question 44

_________ of the iris stroma provide the color of one’s eyes

Answer 44

Melanocytes

Question 45

__________ is a transparent biconvex structure suspended immediately behind the iris, which focuses light on the retina

Answer 45

Lens

Question 46

Collagen type of lens capsule

Answer 46

Type IV

Question 47

Provides the place of attachment for the fibers of the ciliary zonule

Answer 47

Lens capsule '

Question 48

Lens epithelium is composed of ______ cells

Answer 48

Single layer of cuboidal (anterior surface only)

Question 49

True or False: At the posterior edge of lens epithelium, near the equator of the lens, the epithelial cells divide to provide new cells that differentiate as lens fibers. This process allows for growth of the lens and continues at a slow, decreasing rate near the equator of the lens throughout adult life.

Answer 49

True

Question 50

True or False: Lens fibers develops from lens epithelium.

Answer 50

True

Question 51

This fills the cytoplasm of lens fiber

Answer 51

Crystallin

Question 52

True or False: Lens fibers are packed loosely together and form a perfectly transparent tissue highly specialized for light refraction.

Answer 52

False, tightly

Question 53

The lens is held in place by fibers of the _________.

Answer 53

Ciliary zonule

Question 54

When the eye is at rest or gazing at distant objects, ciliary muscles_______ and to focus on a close object the ciliary muscles ______

Answer 54

Relax | Contract

Question 55

Condition that normally causes the lenses to lose elasticity and their ability to undergo accommodation.

Answer 55

PRESBYOPIA

Question 56

It occupies the large vitreous chamber behind the lens. It consists of transparent, gellike connective tissue that is 99% water (vitreous humor)

Answer 56

Vitreous body

Question 57

The only cells in the vitreous body which synthesize the hyaluronate and collagen, and a few macrophages.

Answer 57

Hyalocytes

Question 58

Layers of retina

Answer 58

Outer pigmented layer | Inner neural layer

Question 59

Epithelium of pigmented layer of retina

Answer 59

simple cuboidal epithelium

Question 60

Retinal layer that is thick and stratified with various neurons and photoreceptors.

Answer 60

Neural layer