Eye

Question 1

Neurons devoted to visual processing take up about ________ percent of the cortex.

Answer 1

30

Question 2

The anterior cavity is between the _______ and the ________ whereas the anterior chamber is between the cornea and iris

Answer 2

Cornea, lens

Question 3

Due to the cornea being avascular, it receives much of its oxygen and nutrients from ________.

Answer 3

Tears

Question 4

The choroid plexus within the ciliary body secretes ________/min of aqueous humor.

Answer 4

2μl

Question 5

Aqueous humor is replaced every ________.

Answer 5

2 hours

Question 6

The trabecular meshwork of the eye causes resistance and creates a pressure of ________.

Answer 6

15 mmHg

Question 7

What are the two possible anatomical causes of glaucoma?

Answer 7

Iris and lens pinch off space between anterior and posterior chamber

Canal of Schlemm is blocked

Question 8

Cone pigments are called ________ and rod pigments are called ________.

Answer 8

Photopsins, rhodopsins

Question 9

Protanopia is color blindness due to lack of ________ pigment. It is found on the ________ chromosome.

Answer 9

Red, X

Question 10

Deuteranopia is color blindness due to lack of ________ pigment. It is found on the ________ chromosome.

Answer 10

Green, X

Question 11

Tritanopia is color blindness due to lack of ________ pigment. It is found on the ________ chromosome.

Answer 11

Blue, seventh

Question 12

Müller cells expand across the entire length of the ________ and provide ________ support to the other neuronal cells.

Answer 12

Retina, structural

Question 13

Müller cells enhance the ________ ratio and ________ intraretinal light scattering

Answer 13

Signal/noise, minimize

Question 14

Horizontal cells are found in the ________.

Answer 14

Inner nuclear layer

Question 15

Horizontal cells ________ inputs from photoreceptors and provide ________ to photoreceptors.

Answer 15

Summate, negative feedback

Question 16

Bipolar cell nuclei are found within the ________.

Answer 16

Inner nuclear layer

Question 17

Bipolar cells are responsible for connecting ________ with ________ cells, ________ cells, and ________ cells.

Answer 17

Photoreceptors, ganglion, amacrine, horizontal

Question 18

What is the ratio of cones:bipolar cells:ganglion cells in the fovea?

Answer 18

1:1:1 (for best visual acuity)

Question 19

In the periphery, bipolar cells could potentially collect stimuli from up to 50 rods at one time. This is known as ________.

Answer 19

Low illumination convergence

Question 20

________ cells are short, have a large round cell body, and do not have long axons or dendrites.

Answer 20

Amacrine

Question 21

Amacrine cells are ________ and are responsible for modulating, connecting, and integrating signals presented to _________ cells.

Answer 21

Interneurons, ganglion

Question 22

Amacrine cells are located within the ________ and express a large number of ________.

Answer 22

Inner nuclear layer, neurotransmitters

Question 23

The axons of ________ cells form the optic nerve and connect with the ________ of the thalamus.

Answer 23

Ganglion, lateral geniculate nucleus

Question 24

Which two cell types of the retina are non-neuronal?

Answer 24

Müller and myo/nog cells

Question 25

Myo/nog cells are located along areas with retinal ________. They are typically found in low numbers but will increase when the retina is ________.

Answer 25

Vasculature, stressed

Question 26

The role of myo/nog cells is ________.

Answer 26

Neuroprotective

Question 27

Retinitis pigmentosa mainly affects ________ photoreceptors and causes difficulty with ________ vision.

Answer 27

Rod, peripheral

Question 28

The layer behind the retinal pigment epithelium thickens and yellow deposits appear in what disease?

Answer 28

Age related macular degeneration

Question 29

The pigment layer of the retina is supplied by the ________ whereas the neuronal layers of the retina are supplied by the ________.

Answer 29

Choriocapillaris (from the posterior ciliary arteries), capillary plexus from the central retinal artery

Question 30

Photoreceptors have the ________ metabolic rate in the body.

Answer 30

Highest

Question 31

What does surface ectoderm give rise to?

Answer 31

Lens Lacrimal gland Conjunctiva Epithelium of cornea Epidermis of eyelids

Question 32

What does neural tube become?

Answer 32

Optic vesicle and cup Retinal pigment epithelium Ciliary body epithelium Sphincter pupillae, dilator pupillae Optic nerve fibers, glia

Question 33

What does neural crest become?

Answer 33

Cornea endothelium Trabecular meshwork Stroma of iris and choroid Ciliary body Vitreous and optic nerve meninges

Question 34

What does mesoderm become?

Answer 34

Vitreous Extraocular muscles Ciliary muscle Orbital and ocular vascular endothelium

Question 35

Development of the retinal cells are in what order?

Answer 35

1) retinal pigment epithelial 2) ganglion 3) horizontal 4) cones 5) amacrine 6) bipolar 7) rods 8) müller (Get Her a CAB Ride Man)

Question 36

The lens grows in size due to division of cells at the ________.

Answer 36

Equator

Question 37

The outer rim of the optic cup forms the ________.

Answer 37

Iris

Question 38

At the rim of the optic cup, the two layers begin to fold and result in the formation of the ________.

Answer 38

Ciliary processes

Question 39

________ induces ________ and is essential for the development of the eye and the retina.

Answer 39

Noggin, PAX6

Question 40

What are some congenital eye defects and what are they caused by?

Answer 40

Retinal detachment/non-attachment: failure of the intraretinal space to fuse Cyclopia: abnormal signaling Cataract: transcription factor mutations Chorioretinitis: viruses Microphthalmia: transcription factor mutations Coloboma: failure of choroidal fissure closure