It is thought that life arose on earth around four billion years ago. The endosymbiotic theory states that some of the organelles in today's eukaryotic cells were once prokaryotic microbes.
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Benign means that the growth doesn’t spread to other parts of the body and the tumor is noncancerous.
Behavioral responses in complex organisms requires coordination and communication between CELLS, ORGANS, ORGAN SYSTEMS AND THE WHOLE ORGANISMS.
Behaviour refers to the kind of response that an organism can make to an internal stimulus or an external stimulus. Behavioural responses in complex organisms requires all the levels of organizations that make up the system.
