In what organisms are you referring to?
Just workout whole body 3 times a week
This can be because of their genetics. The siblings may not have inherited their parents looks, but maybe they inherited their grandparents looks, or even their aunts looks. This is all due to genetics. It's sort of the same thing, when two caucasian parents have an african-american child. That would be because somewhere along the family tree someone was african-american.
Anyways, I hope this helps!
Well its a little deeper than that. The oxygen transport is made through Hemoglobin (red blood cells) which is pumped from the heart
