The esophagus has to be flexible to allow for food to travel from the mouth to the stomach
Answer:
Explanation:
From the question we are told that
2 species
Assuming that questions a and be are solved
Diversity index D=2p_1p_2
with 
Mathematically



Therefore

Giving

We have been able to see more of the cell in detail. We dont have to guess about things because we can see how it works. The more we see the more theories change because we know more.