Eye

Question 1

Sclera

Answer 1

White of eye
Protects and maintains eye shape
Becomes cornea

Question 2

Cornea

Answer 2

Focused bending light towards pupil and protect (no blood supply nutrient obtained from aqueous humour)

Question 3

Aqueous humid

Answer 3

Maintains shape, nourishes cornea and focus light

Question 4

Iris

Answer 4

Muscular coloured part

Question 5

Ciliary muscle

Answer 5

Adjusts shape of lens (accommodation)

Question 6

Vitreous Humour

Answer 6

Maintains shape and light focus

Question 7

Retina

Answer 7

Back of eye w photoreceptors

Question 8

Choroid coat

Answer 8

Below sclera

Contains blood vessels and black pigment making eye interior look black and prevents light from scattering

Question 9

Conjunctiva

Answer 9

Thin membrane w lots of blood vessels

Question 10

Fovea centeralis

Answer 10

High cone density=detailed vision

Question 11

Focusing

Answer 11

Light is focused on retina but clearest image on fovea

Image is mirrored and upside down

Question 12

Accommodation

Answer 12

Changing lens shape to focus

Far- ciliary muscle relax= lens thin and flat

Near- Cm contract= lens fat and round

Question 13

Compare and contrast rods and cones (Location in retina, Optimal light, Visual acuity, Colour sensitivity, Type of vision, # of types, Abundance)

Answer 13

Rods:
Location in retina- Periphery
Optimal light- Dim
Visual acuity- Low resolution (many rods: 1 bipolar cell)
Colour sensitivity- All wavelengths
Type of vision- Acromatic
# of types- One contain rhodopsin
Abundance- Many

Location in retina- Fovea
Optimal light- Bright
Visual acuity- High resolution (1 cone:1 bipolar cell)
Colour sensitivity- red green and blue
Type of vision- colour
# of types- 3 iodopsin pigments
Abundance- fewer

Question 14

Why are rods effective in dim light

Answer 14

Sensitive to light (bright light=temporary bleaching)

Question 15

What happens when light hits rhodopsin (what is its composition) in rods

Answer 15

When light hits Rhodopsin (retinene (vitamin a derivative and opsin) its splits apart= transmission of inhibitory neuroTM stopped allowing AP

Question 16

How do cones work and their composition

Answer 16

Made of photopsin/ iodopsin (red green blue)

Less light sensitive so it needs a lot of light hence it works in bright light

Each cone stimulated at diff wavelength

Question 17

What do rods and cones synapse w

Answer 17

Bipolar cells

Question 18

What happens when rods and cones are stimulated bs unstimulated

Answer 18

Not stimulated- releases inhibitory neuroTM and hyper polarizes bipolar cell so no signal is sent to ganglion

If stimulated no inhibitory signal sent to ganglion are activated

Question 19

Transmission of light

Answer 19

Direction of light in retina:
Ganglia to bipolar cell to photoreceptors

Direction of impulse:
Photoreceptors to bipolar cells to ganglion cell

Brain:
Optic nerve to lateral geniculate nucleus to visual cortex nucleus

Question 20

Ganglion cells

Answer 20

Send signal to brain by optic nerve (blind spot)

It’s dendrites synapse w bipolar cells
It’s axon pass through retina where it meets optic

Question 21

Transmitting signal to brain

Answer 21

Left occipital loves gets info from right part of vision

Question 22

Function of bipolar cells

Answer 22

Intermediate between photoreceptors and ganglion