receptors in the eye
- Created by: izzychaloner123
- Created on: 17-02-15 10:49
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- receptors in the eye
- found in the innermost layer: the retina
- Rod Cells
- cannot distinguish between different wavelngths
- can only see in back and white
- There are more Rod cells and cone cells in the eye
- can only see in back and white
- many rod cells are attached to one neurone
- so can respond to light of very low intensities
- a threshold must be overcome to produce a generator potential
- more likely to overcome the threshold as many rod cells are attached to one bipolar cell
- a threshold must be overcome to produce a generator potential
- so can respond to light of very low intensities
- cannot distinguish between different wavelngths
- Cone Cells
- There are three different wavelengths of light
- depending on the proportion of each type that is stimulated
- so we can perceive images in full colour
- depending on the proportion of each type that is stimulated
- there are 6 million cone cells
- each has its own bipolar cell
- cone cells only respond to high light intensity
- The pigment idopsin requires a higher light intensity
- cannot see at night
- the brain can distinguish between the two separate impulses
- two dots together will appear as two dots
- has high visual acuity
- two dots together will appear as two dots
- the brain can distinguish between the two separate impulses
- cannot see at night
- The pigment idopsin requires a higher light intensity
- cone cells only respond to high light intensity
- each has its own bipolar cell
- There are three different wavelengths of light
- to create a generator potential the pigment rhodopsin must be broken down
- low intensity light is needed to cause the breakdown
- many rod cells to one bipolar cell will only generate one impulse
- no matter how many neurones are stimulated
- they cannot distinguish between the sources of light that stimulated them
- two dots together will appear as a single blob
- rod cells have low visual acuity
- at the peripheries of the retina only rod cells are found
- rod cells have low visual acuity
- two dots together will appear as a single blob
- they cannot distinguish between the sources of light that stimulated them
- no matter how many neurones are stimulated
- many rod cells to one bipolar cell will only generate one impulse
- low intensity light is needed to cause the breakdown
- distribution of rod and cone cells on the retina is uneven
- fovea has the highest intesnsity of light
- by having different types of light receptors, each reponding to differnt stimuli, mammals can benefit from good vision in night and day
- fovea has the highest intesnsity of light
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