Question

What do you mean by ommatidia

Answer 1

Hey mate here is your answer

Ommatidia:- each of the optical units that make up the compound eye of an insect.

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Answer 2

The compound eyes of arthropods like insects, crustaceans and millipedes are composed of units called ommatidia(singular: ommatidium). An ommatidium contains a cluster of photoreceptor cellssurrounded by support cells and pigment cells. The outer part of the ommatidium is overlaid with a transparent cornea. Each ommatidium is innervated by one axon bundle (usually consisting of 6-9 axons, depending on the number of rhabdomeres) and provides the brain with one picture element. The brain forms an image from these independent picture elements. The number of ommatidia in the eye depends upon the type of arthropod and may be as low as 5 as in the Antarctic isopod Glyptonotus antarcticus or range from just a handful in the primitive Zygentoma to around 30 thousand in larger Anisoptera dragonflies as well as in some Sphingidae moths.