Answer:
A is pointing to the cell membrane. The cell membrane's main function is to provide protection for the cell as well as allow substances in and out of the cell due to selective permeability.
Explanation:
Some other functions:
-Endocytosis and Exocytosis
-Cell Signaling
Answer:
identify the variables
Explanation:
control:type of lemon used
dependent:whether apple slice turns brown at pH>2
independent:pH value
answer B) eact new cell has fewer chromosomes in it's nucleus