Physio - Optical properties of Eye & Vision

Question 1

Which layer of the retina contains the Cell bodies of rods & cones?

Answer 1

Outer Nuclear Layer (ONL)

Question 2

Which layer of the retina contains the Nuclei of horizontal, bipolar and amacrine cells ?

Answer 2

Inner Nuclear Layer

Question 3

What structures are found in the Outer Plexiform layer?

Answer 3

Rod and cone axons
Horizontal cell dendrites
Bipolar dendrites

Question 4

Which layer of the retina axons of bipolars (and amacrines), dendrites of ganglion cells ?

Answer 4

Inner Plexiform Layer

Question 5

Which structures are found in the Layer of the Ganglion cells?

Answer 5

Nuclei of the ganglion cells and displaced amacrine cells .

Question 6

Fill in the blanks.” ___________________ connect receptor cells to other receptor cells in the outer plexiform layer. “

Answer 6

Horizontal cells

Question 7

Fill in the blanks. “ ________________ connect ganglion cells to one another in the inner plexiform layer.”

Answer 7

Amacrine cells

Question 8

Which region of the highest visual activity of the retina?

Answer 8

Fovea

Question 9

True or False? The Fovea is the centre of the retina .

Answer 9

TRUE!!

Question 10

Fill in the blanks. “ _______________ are black /white receptors.”

Answer 10

Rods

Question 11

What is the functions of the Rods?

Answer 11

To detect motion, responsible for peripheral vision, low-light vision.

Question 12

True or False? In the retina , Light BLOCKS cGMP binding.

Answer 12

TRUE!!

Question 13

Fill in the blanks. “ _____________ need bright light for activation (photopic vision) while ___________ are inactive during the day ( Scotopic vision) .

Answer 13

CONES - need Bright light ( Photopic vision )

RODS- are inactive during the day ( Scotopic vision )

Question 14

Fill in the blanks. “ Cones are found in the ___________ and concentrated in the __________.”

Answer 14

Cones are found in the Macula Lutea, concentrated in the Fovea Centralis.

Question 15

True or False? There are more Cones than Rods in the eyes.

Answer 15

FALSE!! There are more Rods in the eyes than cones.

120 milli in eye ( rods)
6 milli in eye (cones)

’ Rods rules!!’

Question 16

True or False? Photopic vision ( Cones) distinguishes shapes and colors while Scotopic vision ( Rods) distinguishes shapes but not colors.

Answer 16

TRUE!!

Question 17

Which vision is used at night when the light intensity is LOW?

Answer 17

Scotopic vision

Question 18

Which bipolar cells are Glutamate INHIBITORY to ?

Answer 18

On- Centre( H) bipolar cells

Question 19

Which bipolar cells are Glutamate is EXCITATORY to?

Answer 19

Off- Centre ( D) bipolar cells

Question 20

Where are midget bipolar cells concentrated?

Answer 20

In the Fovea

Question 21

Fill in the blanks. “ Rods bipolar cells listen to _________.”

Answer 21

15-45 rods

Question 22

Fill in the blanks. “ Cone bipolar cells listen to ________.”

Answer 22

5-20 adjacent cones

Question 23

Which cells play a role in “ centre/sound detection”?

Answer 23

Horizontal cells

Question 24

Fill in the blanks. “ ___________ release GABA continuously if NOT activated but when they become activated by receptors they cease GABA release preventing the cone and rod receptors from signaling light detection.”

Answer 24

Horizontal cells

Question 25

What is the best stimulus for Horizontal cells?

Answer 25

Illumination of a large area of retina.

Question 26

Fill in the blanks. " Rod bipolar cells do not connect directly to ganglion cells, but rather indirectly via __________."

Answer 26

Amacrine ( non-polar) cells

Question 27

Which cells are the output of the retina and are known as the 'on'& 'off' centre receptive cells?

Answer 27

Ganglion cells

Question 28

True or False? M cells are Not colour sensitive and handle low contrast.

Answer 28

TRUE!!

Question 29

What is the Visual pigment of Rods?

Answer 29

Rhodopsin (opsin + 11-cis retinal)

Question 30

Fill in the blanks. " 11-cis retinal + opsin regenerate __________."

Answer 30

Rhodopsin

Question 31

Which colour is Rhodopsin most sensitive to?

Answer 31

Blue-Green

Question 31

Fill in the blanks. " Ganglion cells of the retina project their axons towards the ___________ of the eye."

Answer 31

Posterior pole

Question 32

What layer numbers are Magnocellular layers?

Answer 32

Layers 1&2

Question 33

What layer numbers are Parvocellular layers?

Answer 33

3,4,5& 6

Question 34

Small visual field deficits are called?

Answer 34

Scotomas

Question 35

Large visual field deficits are called?

Answer 35

Anopsias.

Question 35

The amount of light entering the eye is controlled by the?

Answer 35

Iris

Question 36

Iris muscles are controlled by ANS. Fill in the blanks ' PNS innervate ___________ while SNS innervate _____________ .'

Answer 36

PNS innervate circular muscle SNS innervate radial muscle

Question 37

Fill in the blanks. " ______________ causes circular muscles of the eye to contract."

Answer 37

Parasympathetic stimulation

Question 38

Fill in the blanks. " ________________ causes radial muscles to contract ."

Answer 38

Sympathetic stimulation

Question 39

What is the name given to the pathology when a patient has loss of central vision?

Answer 39

Central Scotoma