Thursday, March 5, 2020

SHORT NOTES ON PECTEN

In pigeon eye projecting into the vitreous body from the blind spot, a characteristic comb like structure  is present. It is called pecten. The pecten is highly variable in size and shape in different birds. In pigeon, it is composed of a thin dark pigmented plate which is folded fanwise and assumes the form of a comb.p
Pecten is made up of a vascular network supported by pigmented cells. The physiological role of pecten is not yet detailed. Pecten is claimed to perform a number of functions in  pigeon.

The functions of pecten are:
(1) The irregular shad­ows cast by this organ provide many blind spots on the retina which enhances the on-and-off effects in the visual field and thus increases the keenness of visual perceptions.
(2) The pecten helps in the nutrition of vitreous body and retina.
(3) The pecten helps to protect the retina from strong light.
(4) Some scientists argued that it helps in the process of accommodation. 

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