Answer:
Listen to pronunciation. (al-VEE-oh-ly) Tiny air sacs at the end of the bronchioles (tiny branches of air tubes in the lungs). The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out.
Answer:
<u><em>Ancestors</em></u>
Explanation:
Ancestors can be described as the persons from which a particular human being originated. In a broader perspective, it is referred to family history of a person. Scientists believe that all organisms on Earth originated from a common ancestor which were the prokaryotes. The prokaryotes with time gave rise to the eukaryotes. Common descent is the phenomenon in which organisms having common ancestors are referred.
I may be wrong but I think it’s the second one. They speed up reactions, and there’s a certain enzyme for a certain reaction.
