The one challenge for biology right now is:
Biologists are always seeking better tools for imaging the body and the
brain. Many mysteries remain in the catalog of human genes involving exactly how genes work in processes of activation and inhibition.
Answer
A) use them to expel excess water from the cell
Answer: a metric unit of mass equal to one thousandth of a kilogram
Explanation:
1. The alveoli are adapted to make gas exchange in lungs happen easily and efficiently.
2. They have moist, thin walls (just one cell thick) they have a lot of tiny blood vessels called capillaries.