Special Senses pt. 2

Question 1

more than half of the sensory receptors in the human body are located in the

Answer 1

eyes

Question 2

what part of the brain is strongly dedicated to processing visual info

Answer 2

cerebral cortex

Question 3

what is visible light according to electromagnetic radiation that is detected by eyes

Answer 3

between 400 - 700 nm

Question 4

what are the accessory structures of the eyes (4)

Answer 4

eyelids, eyelashes & eyebrows, lacrimal apparatus, extrinsic eye muscles

Question 5

functions of the eyelids

Answer 5

shade the eyes during sleep, protects the eyes form excessive light and foreign object, and spreads lubricating secretions over the eyeballs

Question 6

from superficial - deep, name layers of the eyelid

Answer 6

epidermis, dermis, subq tissue, fibers of the orbicularis oculi muscle, tarsal plate, tarsal glands, and conjunctiva

Question 7

thin mucous membrane that lines the inner aspect of the eyelids and is reflected onto the anterior surface of the eyeball

Answer 7

conjunctiva

Question 8

functions of the eyelashes and eyebrows

Answer 8

helps protect the eyeballs from foreign object, perspiration, and direct rays of the sun

Question 9

function of the lacrimal apparaus

Answer 9

produce and drains tears

Question 10

pathway for tears

Answer 10

lacrimal glands > lacrimal ducts > lacrimal puncta > lacrimal canaliculi > lacrimal sac > nasolacrimal ducts

Question 11

how many extrinsic eye muscles are there; name them

Answer 11

6; superior rectus, inferior rectus, lateral rectus, medial rectus, superior oblique and inferior oblique

Question 12

3 layers of the eye

Answer 12

fibrous tunic, vascular tunic, retina

Question 13

2 regions of the fibrous tunic

Answer 13

posterior sclera and anterior sclera

Question 14

“white” of the eye; gives shape to the eyeball and protects its inner parts

Answer 14

sclera

Question 15

nonvascular, transparent, fibrous coat through which iris can be seen, acts in refraction of light

Answer 15

cornea

Question 16

3 portions of the vascular tunic

Answer 16

choroid, ciliary body, iris

Question 17

absorbs light rays so that they are reflected and scattered within the eyeball; provides nutrients to the posterior surface of the retina

Answer 17

choroid

Question 18

what makes up the ciliary body

Answer 18

ciliary processes and ciliary muscle

Question 19

smooth muscle that alters the shape of the lens for near or far vision

Answer 19

ciliary muscle

Question 20

colored portion seen through the cornea

Answer 20

iris

Question 21

black hole in the center of the iris; where light enters the eyeball

Answer 21

pupil

Question 22

principal function of the iris

Answer 22

regulate the amount of light entering the posterior cavity of the eyeball

Question 23

what part of the eye is the beginning of the visual pathway

Answer 23

retina

Question 24

point at which the optic nerve exits the eye

Answer 24

optic disc

Question 25

what makes up the retina

Answer 25

pigment epithelium, and neural portion

Question 26

aids the choroid in absorbing stray light rays

Answer 26

pigment epithelium

Question 27

neural portion contains 3 zones of neurons that are named in the order in which they conduct nerve impulses:

Answer 27

photoreceptor neurons, bipolar neurons, and ganglion neurons

Question 28

photoreceptor neurons

Answer 28

rods and cones

Question 29

inferior of the eyeball is a large space divided into 2 cavities by the lens:

Answer 29

anterior cavity, and the vitreous chamber

Question 30

what fills the anterior cavity

Answer 30

aqueous humor

Question 31

flow of aqueous humor

Answer 31

posterior chamber > pupil > anterior chamber > scleral venous sinus (canal of Schlemm) > blood

Question 32

what is produced by the aqueous humor

Answer 32

intraocular pressure

Question 33

increase in the curvature of the lens, initiated by ciliary muscle contraction, which allows the lens to focus on near objects

Answer 33

accomodation

Question 34

myopia

Answer 34

nearsightedness; concave lens

Question 35

hyperopia

Answer 35

farsightedness; convex lens

Question 36

refraction abnormality d/t an irregular curvature of either the cornea or lens

Answer 36

astigmatism

Question 37

visual pathway

Answer 37

impulses from ganglion cells > retina > optic nerve > optic chiasma > optic tract > thalamus > occipital lobes of the cortex

Question 38

light pathway

Answer 38

light > cornea > anterior chamber > pupil > posterior chamber > lens > vitreous humor > retina