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The key points covered of this video include:

1. Visual Resolution of Peripheral Vision
2. Visual Resolution of Central Vision
3. Distribution of Rods and Cones

Visual Resolution of Rod Cells

The resolution of our vision changes in different environments. Our visual resolution is lowest in the peripheral vision. This is because this part of the retina contains mostly rod cells.Multiple rod cells connect to a single bipolar cell. If light hits one rod cell, it causes an action potential in the bipolar cell which is sent to the brain. If light hits a different rod cell connected to the same bipolar cell it will cause the same response. The brain has no way of determining which rod cell the signal came from since the bipolar cell response is the same. This lowers the resolution of the image since the exact location of the light cannot be determined.

Visual Resolution of Cone Cells

The visual resolution of the eyes is highest in the fovea. This part of the retina contains mostly cone cells. Each bipolar cell is connected to a single cone cell. When a photoreceptor stimulates the bipolar cell the signal will be sent to the brain. The brain can interpret the signal as coming from that exact cone cell. This means cone cell signals have higher resolution, since the location of light can be pinpointed more accurately.

Distribution of Rods and Cones

The parts of the retina furthest away from the fovea contain mostly rod cells. As well as multiple rod cells being connected to a neurone, rod cells are less dense in the fovea. This means that peripheral vision has lower resolution. This means the centre of the vision is in higher resolution.

Summary

The peripheral vision contains mostly rod cells while the fovea contains mostly cone cells
Multiple rod cells connect to a single bipolar cell, this means the brain cannot interpret which photoreceptor the signal comes from
Single cone cells cells connect to single bipolar cells, meaning the brain can interpret exactly where in the retina the image came from
Rod cells are less dense in the retina, while cone cells are more dense
This rod cell vision is blurry and cone cell vision is more clear