Special Sense Organs Part 3

Question 1

Where are the tarsal glands located?

Answer 1

in each eyelid

Question 2

What kind of gland are the tarsal glands?

Answer 2

sebaceous glands that secrete an oily substance that covers the eyes upon blinking

Question 3

What is the purpose of the oily substance produced by the tarsal glands?

Answer 3

reduces evaporation of tears

Question 4

All arteries of the eyeball are branches of what artery?

Answer 4

ophthalmic artery

Question 5

Where are the long posterior ciliary arteries located?

Answer 5

one on each side of the eye running between the sclera and the choroid

Question 6

How many short ciliary arteries enter the eyeball on the posterior surface forming a ring around the optic nerve?

Answer 6

six to twelve

Question 7

How many anterior ciliary arteries arch over or under the eyeball?

Answer 7

six to eight (3 or 4 over and 3 or 4 under)

Question 8

What artery travels via the optic nerve to the retina where it spreads out into an extensive network? It is the only artery to supply the retina.

Answer 8

Central retina artery

Question 9

T/F: A thrombus/embolism in the central retinal artery will not result in blindness in that artery.

Answer 9

False; at least some blindness will result in that eye .No redundancy in blood supply to a single retina

Question 10

What are the 3 sources of venous drainage for the eye?

Answer 10

anterior ciliary, long posterior ciliary, and central retinal veins

Question 11

T/F: veins of the eye accompany arteries of similar names? i.e. anterior ciliary artery and anterior ciliary vein

Answer 11

True

Question 12

What branches of the nasociliary nerve of the ophthalmic division of the trigeminal nerve provide nerve supply to the eyeball?

Answer 12

long ciliary nerves and short ciliary nerves

Question 13

What nerves supply sensory info for the ciliary body, iris, and cornea?

Answer 13

long ciliary nerves

Question 14

What nerves supply sensory info for the eyeball?

Answer 14

short ciliary nerves

Question 15

What kind of fibers from the cavernous plexus pass through the ciliary ganglion and reach the ciliaris and dilator pupillae muscles?

Answer 15

postganglionic sympathetic fibers

Question 16

What fibers from the ciliary ganglion follow a similar path to the ciliaris and sphincter pupillae muscles?

Answer 16

postganglionic parasympathetic fibers

Question 17

What structure is known as an ectodermal thickening called the placode during embryological development?

Answer 17

ear

Question 18

After the placode invaginates, it gives rise to the auditory pit which is then called what?

Answer 18

auditory vesicle

Question 19

What “business part” will the auditory vesicle give rise to?

Answer 19

most of the membranous inner ear

Question 20

What are the auditory tube and tympanic cavity derived from?

Answer 20

first pharyngeal pouch

Question 21

What is the malleus derived from?

Answer 21

dorsal end of the ventral mandibular cartilage

Question 22

What does the incus develop from?

Answer 22

dorsal end of the first pharyngeal arch

Question 23

What is the stapes derived from?

Answer 23

dorsal end of the second pharyngeal arch

Question 24

What is the tympanic membrane developed from?

Answer 24

interstitial mesoderm

Question 25

What does the external acoustic canal develop from?

Answer 25

first pharyngeal groove

Question 26

What does the auricle develop from?

Answer 26

a groove next to the first pharyngeal groove

Question 27

What portions make up the ear?

Answer 27

external, middle, and inner portions

Question 28

What is included in the external ear?

Answer 28

auricle and external acoustic meatus

Question 29

What horn-like structure funnels sound waves, is composed of cartilage and is also known as pinna?

Answer 29

Auricle

Question 30

What three extrinsic muscles position the auricle?

Answer 30

anterior, superior, and posterior auricular muscles

Question 31

What is the smallest extrinsic muscle positioning the auricle? largest

Answer 31

anterior auricular muscle;

superior auricular muscle

Question 32

What is the extrinsic muscle, which helps position the auricle, that inserts on the lower, posterior aspect of the concha?

Answer 32

posterior auricular muscle

Question 33

What are the 6 intrinsic muscles of the auricle?

Answer 33

helicis major, helicis minor, tragicus, antitragicus, transverse muscle of the auricle, and oblique muscle of the auricle