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.

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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.

Insect Blood

The blood of an insect functions differently than the blood of a human. In humans, blood gets its red color from hemoglobin, which travels through blood vessels carrying oxygen from the lungs to the rest of the body. Insect blood, however, does not carry gasses and has no hemoglobin. Instead, bugs have a system of tubes that transport gasses directly between their cells and the outside air.

In fact, insects don’t even have blood vessels. Instead there is a hollow space inside their external skeleton in which their blood oozes around. This cavity extends to the antennas, legs, and wing veins. The bug’s heart, a long tube that stretches the length of its body, pushes the blood from the rear end of the insect on forward. The bug may also have little hearts at the ends of its extremities to help move the blood along.

Pigment

Pumping blood is a slow process: it takes about eight minutes for an insect’s blood to circulate completely. Like human blood, bug blood carries nutrients and hormones to the insect’s cells. The greenish or yellowish color of insect blood comes from the pigments of the plants the bug eats.