Question

What is regeneration? Give one example of an organism that shows this process and one organism that does not. Why does regeneration not occur in the latter?

Hint:

Regeneration is most effective in organisms with simpler body structures, like starfish, and is less common in complex organisms such as humans.

Answer 1

Regeneration: Regeneration is the biological ability of an organism to regrow lost or damaged body parts. It's a type of asexual reproduction where new cells develop and specialize to replace lost parts. Example: The starfish demonstrates regeneration. A starfish can regrow an arm from a remaining body part if it's lost.
Example of no regeneration: Humans do not regenerate lost limbs. 
Why humans lack regeneration: Humans have a complex body structure with specialized cells. Regeneration requires undifferentiated cells, which is limited in humans because of their complex cell differentiation and repair processes.