Eye & Retina

Question 1

What is light?

Answer 1

Visible electromagnetic radiation

Question 2

What is the canal of Schlemm?

Answer 2

Drains fluid produced from ciliary bodies around the lens

Question 3

What is the refractive index of air?

Answer 3

1

Question 4

What is cataracts?

Answer 4

Cloudy lens

Question 5

What is glaucoma?

Answer 5

Increased eye pressure, reduced blood supply leads to retinal degeneration

Question 6

What does the iris do?

Answer 6

• Regulates light levels
• Pupillary constrictor
• Pupillary dilator

Question 7

What kind of muscle aids in the iris during pupillary constriction?

Answer 7

Smooth circular muscle

Question 8

What kind of muscle aids in the iris during pupillary dilation?

Answer 8

Smooth radial muscle

Question 9

Cranial nerve III

Answer 9

Occulomotor

Question 10

Cranial nerve II

Answer 10

Optic nerve

Question 11

Near response

Answer 11

When you bring an object closer to your eye

Question 12

What is miosis?

Answer 12

Constriction of the pupils of the eyes

Question 13

What is special about the retinas in molluscs?

Answer 13

Retina is built right way round so no image flipping

Question 14

Define scotopic

Answer 14

Vision in low light - low sensitive

Question 15

Define photopic

Answer 15

Vision in daylight - less light sensitive

Question 16

Cones or rod scotopic?

Answer 16

Cones

Question 17

Are rods photopic or scotopic?

Answer 17

Photopic

Question 18

What is the duplicity theory?

Answer 18

Can’t have high sensitivity and high resolution in a single receptor therefore separate systems for colour and monochrome

Question 19

Which photopigment is present in rods?

Answer 19

Rhodopsin

Question 20

Which photopigment is present in cones?

Answer 20

Photopsin

Question 21

Rods or cones for colour?

Answer 21

Cones

Question 22

Phototransduction

Answer 22

In physical notes lol cry

Question 23

What happens to Na+ channels in the photoreceptors that release glutamate in the light? What does this do?

Answer 23

They close thus hyper polarising the receptors, stops inhibiting by glutatmate

Question 24

When is there no glutamate release?

Answer 24

In the light

Question 25

When is glutamate released and what does it inhibit?

Answer 25

In the dark and inhibits bipolar cells

Question 26

"On" bipolar cells

Answer 26

- Hyperpolarised in the dark - Depolarised by illumination - Glutamte inhibits via metabotropic glutamate receptors Conductance increases in light as loss of inhibition by glutamate

Question 27

"Off" bipolar cells

Answer 27

- Depolarised in dark - Hyperpolarised by illumination - Glutamate excites via inotropic glutamate receptors Conductance decreases in light

Question 28

Which kind of bipolar cells are hyper polarised in the dark?

Answer 28

ON bipolar cells

Question 29

Retinal ganglion cell types

Answer 29

- X -mainly cones - W -mainly from rods - Y -inputs less defined - Melanopsin RGCs

Question 30

Rods and cones are the only type of photoreceptive cells in the retina: true or false?

Answer 30

False, refer to EEG and sleep

Question 31

What does light cause photoreceptor Na+ channels to do?

Answer 31

Close