Key Points

• Only one small region of retina, the fovea, provides high visual acuity because the foveal arrangement of photoreceptors places the light-sensitive cellular elements in direct alignment with focused, incoming light.

• Cone photoreceptors are specialized for high-acuity color vision under bright-light (photopic) conditions, whereas rod photoreceptors have more sensitivity but less acuity and are specialized for dim-light (scotopic) vision.

• The retinal pigment epithelium provides a number of crucially important support roles for photoreceptors, including removal of cellular debris and recycling of molecular substrates in the visual transduction cascade.

• The absorption of light by photopigments in rods and cones triggers a phototransduction cascade that ultimately determines the rate at which glutamate is released from photorecep-tor terminals.

• A three-neuron chain consisting of photoreceptor, bipolar, and ganglion cells transmits visual information through the retina, the optic nerve and track, and on to higher visual centers.

• The receptive field of any given neuron in the visual pathway is defined as the portion

Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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