Transductance

Question 1

phototransduction

Answer 1

where engery in light waves (photons) stimulate photorecportor cells on the retina
this is whrer light energy is convted electorchemcia reposnse

Question 2

what is at the base or rods and cones

Answer 2

synaptic ternaiom

Question 3

do rods and cones contain a neucleous

Answer 3

yes

Question 4

what makes up rodes and cones outer segmetn

Answer 4

sacks of discs / lamella which have photoreceptors called rhodopsin in rods

Question 5

what is a a lameella made out of

Answer 5

a cell membarne

Question 6

what makes up the cell membarne of a lamina in rods

Answer 6

visual pigment rhodospin =

Question 7

what makes up the cel membare in cones

Answer 7

opsins s, m and l

Question 8

what are opsin , s, ma and l responsible for

Answer 8

short - s
medium- m
l - large wavelenghts

Question 9

wher eis opsin and retianl found in rhodosoin

Answer 9

intergal transmemare helical protin

Question 10

where is vitamen a found in the eye

Answer 10

in the interagl transmemarb helical proin

Question 11

what type of molcue is vitame a

Answer 11

isomere

Question 12

what caue vitamen a to isomerise

Answer 12

light falling on it

Question 13

what type of vitamen a cannot fit in t th eopsin

Answer 13

all trans retincal

Question 14

what is the opsin

Answer 14

part of the interagl transmemabr helicap proin, the inner part, where retial is

Question 15

what is the normal type of vitamen a in the eye

Answer 15

11 cis retinal (branched )

Question 16

how does the viasl pigment result in phototransducation

Answer 16

phototransudion cascaste

Question 17

what is the role of vit a in the visual pathway

Answer 17

visual regnariton

Question 18

how is vitamen a mainly absobred

Answer 18

throug diet

Question 19

what is the effect of vitamen a diffecty

Answer 19

will cause night blindnes, and damge to the normal epithlum

Question 20

what is the cuase of vit a deficney

Answer 20

malnution
malabsip such as coeliac and spruce

Question 21

signs of vit a dificeny

Answer 21

bitots sposts on conjuctivy
cornela ulcation

Question 22

end stage vit a defecy

Answer 22

corneal melating
opopacification of the cornea

Question 23

what type of cell conects rods to ganglion cell

Answer 23

bipolar nerve cell

Question 24

what color cones are in tehe eye

Answer 24

red, green and blue

Question 25

what is retinal

Answer 25

a vitamen a derivative

Question 26

what is a rhodopsin made of

Answer 26

opsin and retinal

Question 27

bleaching

Answer 27

when the retial changrs shape due to movement of light and no longer binds to opsin

Question 28

what is the name of the catin chanesl in rods

Answer 28

cyclic nucleotide gated channels

Question 29

what do the cyclic neuclotide grated channels do

Answer 29

allow na and ca to enerter k+ to leak out, cand voltage gated ca2+ channels

Question 30

what happens to a rod when it is in darkness to cyclic gmp

Answer 30

cyclic gmp levls become high

Question 31

what is the noramlm depolaris membaner potenal for rjhodopsin in darkness

Answer 31

-40 mv

Question 32

how much neruo transmitter is realed at -40 in rhodpsin

Answer 32

there is alot of nurotaimsitor reese

Question 33

how much nuortramiteor is readxed at -70mv

Answer 33

very little

Question 34

what is the polarisioan of the cell in light

Answer 34

-70mv

Question 35

what is retanl converion

Answer 35

where there are multiple rod cells conencted to one bipoalr cell

Question 36

why is retanl conversion required

Answer 36

as it reduces the threashold for antion pototenal , in low light

Question 37

low visual aquity

Answer 37

hard to see things in low light

Question 38

type of pigment in cone cells

Answer 38

iodopsin - this is what gives it ability to sense colour

Question 39

what type of light intentis cuase idropisn to be broken down

Answer 39

high light instnein

Question 40

where are cones mainly found

Answer 40

in the forvea

Question 41

are rods turned on or off with light

Answer 41

off

Question 42

how many sub using tis rhoedopsin made up of

Answer 42

7

Question 43

noraml retianl before it is changed

Answer 43

7 cis retainal (i.e. it is bent

Question 44

what is the staright retial called

Answer 44

all trans retainal

Question 45

what happens t teh rhodopin after the real hcnate shape

Answer 45

rhodopsin chanes shape

Question 46

what does transducin do

Answer 46

when retianl chanes shape, it break away form rohdopin and joints to pde

Question 47

wat does pde do

Answer 47

changes cyclic gmp to regualr gmp

Question 48

what cause soidum change to open in rod cell

Answer 48

cyclic gmp, so more cyclic gmp mroe soidum enters cell

Question 49

what happens when light hits on teh soudm chell

Answer 49

it decrease due to reduced cyclic gmp and the rods turn off

Question 50

what are the 2 types of bioplar cells

Answer 50

light on and light off bipolar cells light on acitvated by decread decread glutamate dsecion, light on actaved by incerad gluatamt section

Question 51

what is in an rod tip

Answer 51

lots of opttic discs

Question 52

are there more rods or cones

Answer 52

rods - about 20 times more

Question 53

where are rods mainly found

Answer 53

periphally of the eye ball

Question 54

what vitimen is used to transform all trans retinal to 11cis retihnal

Answer 54

vitamen a

Question 55

what is done with the bi products of 11cis regneraiton

Answer 55

becomes retinly esters used for retianl epithelum

Question 56

name for all trans retinal

Answer 56

at rol

Question 57

name for middle step between all trans retail and 11cis retinal

Answer 57

11 cis rol

Question 58

name for 11cis retinal

Answer 58

11 cis ral