Colour of Blood

[himanshu121]

What determines the Colour of BLOOD And why the colour of insects different?

I dont know Biology But i want the answer for above just to add to my knowledge

[Monique]

Haemaglobin is the cause of red blood in vertebrates, as are its derivatives haematin and haematoporphyrin. Insects have a different molecule: hemolymph.

An interesting little fact about insects:
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, and makes a big mess when squashed. 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. And pumping blood is a slow process: it takes about eight minutes for an insect's blood to circulate completely. http://amos.indiana.edu/library/scripts/greenblood.html

[Andy]

Wow monique, thanks for that, it really is true that you learn something knew everyday. Never normally that interesting though.

[Another God]

Is it the Haemoglobin Molecule that is red, or is it the Iron associated with it that makes it red...?

Same question with the Insect blood... Is it the molecule itself, or another contributing factor?

[himanshu121]

Originally posted by Another God
Is it the Haemoglobin Molecule that is red, or is it the Iron associated with it that makes it red...?

Same question with the Insect blood... Is it the molecule itself, or another contributing factor?

The protein is composed of two alpha chains (yellow) and two beta chains (red). Each chain binds a haem group (cyan) which is responsible for binding a molecule of oxygen. The iron atom which binds oxygen is shown as an orange sphere. A fully-loaded haemoglobin molecule binds four oxygen molecules.
from
http://www.bio.ph.ic.ac.uk/molbio/mols/hb/hb.fr.html

I believe it is not due to Iron alone

[himanshu121]

The color of an ion depends on its environment. In aqueous solution ferric irons (Fe3+) are coordinated with six water molecules and have a yellow color rather than the reddish color in case when coordinated with six oxide ions, while the anhydrous chloride is greenish. Fe2+ are green in aqueous solution but that doesn't say much, the presence of nitrogen and oxygen (only oxyhemoglobin is bright red) are going to affect the color significantly. The iron is definitely what is responsible, though, and most brightly colored compounds are made so by coordinated transition metals. And probably due to environment of iron Coordination Complex