Answer:
It is a hypothesis that explains the origin of evolutionary reversions.
Explanation:
A phylogenetic tree may indicate that genes required for forming anatomical structures such as wings are not completely lost and they are activated many times during the evolution.
Answer:a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.
Explanation:
Answer:
The left atrium pumps blood into the lungs!
Explanation:
You could die mitosis has to work in order for your cells to live