Insects have blood but that is not used to carry oxygen. Instead, oxygen is distributed via an elaborate system of tubes and air sacs. Thus, insect blood does not have hemoglobin and is not red. In general, insect blood is either colorless, pale yellow or green.

http://www.harley.com/ask-harley/questions/zoology.html

Thank Mahesh for indicateur of insects blood color.. .

The blood of mollusk is blue; and his pigment contait the CUPRUM.

In man's blood - FERRUM.

Yes most insects are green because they are sensitive to their environment, The life cycle of most insect revolve round of green plant: the egg, the larva, the pupa and the adult. But the green colour is actually from the green plants they reside and feed on.

The grass is green or yellow-green, thus the green color of some insects residing in the field provides perfect disguise

Dear colleges,

Insecte can be not only green (red, gold, etc.) and many -- IRIDESCENCES.

p.s.

Iridescences: The Physical Colors Of Insects was written by Serge Berthier, a French physicist and materials scientist with a passion for beautiful insects.