8

Question 1

is a complex organ, with parts derived from ectoderm and mesoderm in the head
region.

Answer 1

Eye

Question 2

wall, anterior compartment, posterior compartment and lens.

Answer 2

Eyeball

Question 3

intrinsic and extrinsic muscles.

Answer 3

Muscles of the eye

Question 4

The wall of the eye consists of three layers or tunics:

Answer 4

a. Fibrous tunic - cornea and sclera
b. Vascular tunic - choroid, ciliary body and ciliary processes and iris
c. Nervous tunic - retina

Question 5

cornea and sclera

Answer 5

Fibrous tunic

Question 6

choroid, ciliary body and ciliary processes and iris

Answer 6

Vascular tunic

Question 7

retina

Answer 7

Nervous tunic

Question 8

The anterior compartment is composed of

Answer 8

anterior and posterior chambers that contain
aqueous humor.

Question 9

The posterior compartment consists of the

Answer 9

vitreous chamber that contains vitreous
humor.

Question 10

Both eyes develop from the

Answer 10

Optic field

Question 11

by induction from the optic vesicles and placode
formation, thickens to form the

Answer 11

Lens placode

Question 12

cells in the deep or inner pole of the lens elongate to form

Answer 12

Lens fibers

Question 13

Cells in the outer or superficial pole of
the lens form a single layer of cuboidal or columnar epithelium called

Answer 13

Lens epithelium

Question 14

The lens
fibers and lens epithelium produce lens proteins called

Answer 14

Crystallins

Question 15

later on the corneal endothelial cells secrete

Answer 15

Hyaluronic acid

Question 16

That destros the hyaluronic acid

Answer 16

hyaluronidase

Question 17

is the reduced opening of the optic cup

Answer 17

Pupil

Question 18

is derived from the thickened choroid
ectomesenchyme and caudal part of the overlapping portion of the optic cup.

Answer 18

Ciliary apparatus

Question 19

Sorrounding the optic cup

Answer 19

Ectomesenchymal cells

Question 20

which differentiates into the inner vascular later of the
wall called

Answer 20

choroid

Question 21

outer fibrous layer called

Answer 21

sclera

Question 22

In chick, 14 bony rings called

Answer 22

sclera ossicles

Question 23

surround the outer margin
of the cornea.

Answer 23

Sclera ossicles

Question 24

Formed by upper and lower folds of ectoderm (skin), each fold includes a mesenchyme
core.

Answer 24

Eyelids

Question 25

Derived from the space between the eyelid and the cornea.

Answer 25

Conjunctival Sac

Question 26

Develops by invagination and budding of conjunctival ectoderm

Answer 26

Lacrimal Gland

Question 27

Optic vesicle of Dog and Cow

Answer 27

17 days of gestation 25- 30 days of gestation

Question 28

Optic cup of Dog and Cow

Answer 28

19 days of gestation 30 days of gestation

Question 29

Lens vesicle of Dog and Cow

Answer 29

25 days of gestation and 30 days of gestation

Question 30

Fused eyelids of Dog and Cow

Answer 30

33 days of gestation and 50 days of gestation

Question 31

Opening of eyelids of Dog and Cow

Answer 31

14 days after birth and At birth

Question 32

Rods and cornea of retina of Dogs and Cow

Answer 32

16-35 days after birth and 150-180 days of gestation

Question 33

development of a single eye in the center of the head due to failure of the optic field to separate into 2 lateral eye-forming regions

Answer 33

Cyclopia

Question 34

absence of eye due to failure of optic vesicles to form or to severe inference w/ normal growth of optic cup.

Answer 34

Anophthalmia

Question 35

a defect due to failure of the optic fissure to close.

Answer 35

Coloboma

Question 36

small undeveloped eye; results from failure of the vitreous body to exert sufficient pressure for growth, often because a coloboma allowed vitreous humor to escape. Due to Vit. A deficiency in the mother. Common in pig, dog and cattle.

Answer 36

Microphthalmia

Question 37

medial deviation of the eyeball. Common in Siamese Cat

Answer 37

Medial strabismus -

Question 38

contains sense organs for hearing (cochlea) and detecting head acceleration (vestibular apparatus or vesticule), the latter is important in balance. Innervated by the cochlear and vestibular divisions of cranial nerve VIII.

Answer 38

Inner or Internal Ear

Question 39

contains bones (ossicles) that convey vibrations from the tympanic membrane (ear drum) to the inner ear.

Answer 39

Middle Ear

Question 40

channels sound waves to the tympanic membrane.

Answer 40

Outer or External Ear

Question 41

_______of incubation in chick embryo, the surface ectoderm overlying the dorsolateral wall of myelencephalon by___________

Answer 41

35hrs Placode formation

Question 42

of incubation, the otic placodes invaginate to form auditory pits

Answer 42

38hrs

Question 43

of incubation the otic cup closes and separates from the ectoderm (vesicle formation) forming an otic vesicle (otocyst)

Answer 43

50hrs

Question 44

consists of the tympanic membrane, tympanic cavity, auditory ossicles and auditory tube or Eustachian tube.

Answer 44

Middle ear

Question 45

The external ear canal develops from the

Answer 45

1st branchial groove

Question 46

flanking the 1st branchial groove expand laterally to form the wall of the canal.

Answer 46

VA 1 and VA 2

Question 47

is composed of the nasal cavity, alae or wings, bridge, nostrils or anterior nares, choanae or posterior nares, nasal septum and nasolacrimal duct.

Answer 47

Nose

Question 48

is the part of the nose that contains the nasal conchae.

Answer 48

nasal cavity

Question 49

It is divided into right and left chambers by the

Answer 49

Nasal septum

Question 50

is derived from VA 1 and VA 2

Answer 50

Pinna

Question 51

Anterior opening of nasal pit

Answer 51

anterior nares

Question 52

Posterior opening of nasal pit

Answer 52

posterior nares

Question 53

in the midline cephalic to the stomodaeum gives off ectomesenchyme cell to areas between the nasal pits to form the frontal prominence

Answer 53

Frontonasal mesenchyme

Question 54

That develops into the bridge of the nose

Answer 54

Frontal prominence

Question 55

Becomes the nose wings

Answer 55

Lateral nasal processes

Question 56

Right and left medial nasal processes fuse w/ the maxillary processes of the right and left visceral arches 1 to form the

Answer 56

Nasal septum

Question 57

between the lateral nasal process and the maxillary process of the visceral arch 1 deepens to form the nasolacrimal groove.

Answer 57

Depression

Question 58

are groups of specialized (chemoreceptive) epithelial cells localized principally on the papillae of the tongue.

Answer 58

Taste Buds

Question 59

Innervate the taste buds

Answer 59

Cranial nerve VII and IX