OCR A Human Biology The Eye

Hi,

Has anyone got any advice on how to understand rods, cones, bipolar and ganglion cells or any resources?

Many thanks

Basically the rod cells and cone cells are both found in the eye, and they deal with different amounts of light. They are light receptors, and they send the impulses to the brain, creating the image you see.

Going Further question.

What about the fovea? Does it have rods and cones?

The fovea is filled with many cones and no rods (because light is more concentrated here), while the peripheries have all of the rods, and very few (if any) cones.

Bang on! Number of cones falls the further you get from the fovea, so lots in the fovea, lots but not as much in the macula, then less and less the further you get from it.

Thank you

What is the macula? I've heard of this but cannot really remember it.

It's the area around the fovea, basically (this is a bad way of looking at it. Better to think about the fovea being in the macula, rather than the other way around). It's just a yellowy-browny disk located a few degrees off of the optic disc towards the centre - specialised for visual acuity.