What is the chemical composition of the rod pigment, rhodopsin, and how does it appear to act in the reception of light?
What will be an ideal response
Rhodopsin is a combination of retinal and opsin. Retinal is chemically related to vitamin A and is synthesized from it. Retinal can form a variety of three-dimensional forms called isomers. The opsin protein combines with the 11-cis retinal to form rhodopsin. The light-triggered changes in retinal cause hyperpolarization of the rods. This happens because the light turns off sodium entry, which then inhibits the release of neurotransmitter, thus turning off electrical signals.
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Which of the following is not true for ventricular systole?
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