Rhodopsin (1 Viewer)

Mazey

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There's some dotpoint in the syallbus saying to outline its role of rhodopsin in rods!
I have notes scribbled down but they dont really make sense hehe!:rolleyes:
can anyone give us a quick rundown on it?
Thanks!
 

arls

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sure..
Rhodopsin is the photosensitive pigment in rods that is composed of a derivative of Vitamin A called retinal.

When rhodopsin absorbs sufficient light energy, it splits into 2. and stimulates activity of a nerve cell. (In bright lights rhodopsin breaks down quicker than it can be produced, therefore it is only found in the rods not the cones) Rhodopsin is extremly sensitive to light, and is involved in night vision, the slightest amount of light will cause it to break down and stimulate the nerve cells.

thats about all i got on rhodopsin specifically..
hope it helps..
 

swordfish

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Here's my info:
When light strikes the retina, the photoos pass through the layer of ganglion cells, then the bipolar cells, then the rods and cones. In the rods, the rhodopsin absorbs light, causing the retinal part of the molecule to change shape. This in turn causes a change in the shape of the opsin molecule.
This change in the opsin activates a relay molecule called transducin. This ensures less inhibitory neurotransmitter is released into the synapses so an electrical impulse can be transmitted between the rods and bipolar cells, and then between the bipolar cells and ganglion cells. The ganglion cells extend into the optic nerve fibres, which transmit the electrical impulse to the brain.
The opsin and (changed) retinal recombine to form rhodopsin.
 

crazylilmonkee

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actually.. the light hits the rod/cones first... then the bipolar nerve cells then the ganglion.. cos then that leads to the large optic nerve..
 

arls

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Originally posted by crazylilmonkee
actually.. the light hits the rod/cones first... then the bipolar nerve cells then the ganglion.. cos then that leads to the large optic nerve..
thanks for that monkey.... thought i mustve been going crazy cause i thought this was right.. i was too lazy to check though!
 

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