Why do cells have a plasma membrane? A.) to separate proteins from the nucleus
B.) to define the size of the cell
C.) to distinguish plants from animals
D.) to separate the inside of the cell from its environment

D.  to separate the inside of the cell from its environment

Explanation:

The cell membrane is primarily made up of lipids and proteins. It provides protection to the cell by keeping the interior of the cell separated from its external environment.  

It is a selectively permeable membrane meaning that it only allows certain substances to pass through it. It is involved in various cellular processes like cell signaling, cell adhesion, endocytosis, exocytosis etc.

answer: the answer is b

a plastic spoon that has a temperature of 78° f is placed into a bowl of soup that has a temperature of 84° f. which of these correctly describes what will happen?

energy as heat moves from the soup to the spoon.