Cone cell

The retinol that is delivered to the retinas of the eyes in this manner is accumulated by rod and cone cells. In the rods (which are the better characterized of the two cell types), retinol is oxidized by a specific retinol dehydrogenase to become 2iW-trans retinal and then converted to 11-eis retinal by reti-... 

There are two main types of light-sensitive receptor cells in the retina of the human eye, rod cells and cone cells. The 3 million or so rod cells are... 

Concanavalin A, secondary structure of. 1038-1039 Concerted reaction, 1178 Condensation reaction, 882 Condensed structure, 22 Cone cells, vision and, 504-505 Configuration. 297... 

In both worm and fly, the Ras protein acts as a switch that determine cell fate. In C. elegans, the activation of Ras determines the formation of vulval as opposed to hypodermal (skin) cells (for sequence of events, see Table 8.4). In Drosophila photoreceptors, the activation of Ras determines the development of R7 as a neuronal as opposed to a cone cell. In both cases, Ras proteins operate downstream of receptor tyrosine kinases that are activated by cell-cell interactions. 

Light-absorbing pigments differentiate rod cells for black-white vision and three types of cone cells for color vision 807... 

Cone-cell pigments contain different opsins that have high-sequence homology 812... 

The rod and cone cells found in the retina of the eye are functional supramolecular devices involved in information processing. Rod cells function in dim light and are black and white receptors while cones are colour receptors. 

In colour vision there are three specific types of cone cell corresponding to red, green and blue receptors. The chromophore is the same for all three colours, being 11-cis-retinal bound to a protein which is structurally similar to opsin. Colour selectivity is achieved by positioning specific amino acid side chains along the chromophore so as to perturb the absorption spectrum of the chromophore. 

A (carotene) Retinoic acid and retinol act as growth regulators, especially in epithelium Retinal is important in rod and cone cells for vision... 

Rod and cone cells are the light sensitive receptor cells in the retina of the human eye. About three million rod cells are responsible for our vision in dim light, whereas the hundred million cone cells are responsible for our vision in the bright light and for the perception of bright colours. In the rod cells, ll-cw-retinal is converted to rhodopsin. 

Gtl/ Gt2 Photons (rhodopsin and color opsins in retinal rod and cone cells) t cGMP phosphodiesterase - cGMP (phototransduction)... 

Cyclic GMP has a second mode of action in the vertebrate eye it causes ion-specific channels to open in the retinal rod and cone cells. We return to this role of cGMP in the discussion of vision in Section 12.7. 

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