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Unformatted text preview: ciliary body (secretes aequeous humor), rods and cones and retinal pigment epithelium Fields of vision and sensory path to brain: rods or cones, bipolar cells, ganglion cells, amacrine and horizontal cells, lateral geniculate nucleus in the thalamus, cerebral cortex (visual cortex); visual acuity determined by fovea centralis. Light activation of rods (hyperpolarization) leads to action potentials (depolarization) in ganglion cells cis-Retinene + light --> trans-Retinene --> change opsin --> activate transducin --> activate phosphodiesterase --> cleave cGMP to GMP --> block Na channels --> hyperpolarize --> reduce release of inhibitory neurotransmitter --> increase release of excitatory neurotransmitter by bipolar cells --> action potential in ganglion cell Visual cycle and dark adaptation Rods (rhodopsin sensitive to green light preferentially) and cones (three pigments differentially sensitive to red, blue and green light)....
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This note was uploaded on 09/21/2010 for the course MCB 57703 taught by Professor Machen during the Spring '08 term at University of California, Berkeley.
- Spring '08