It allows them to study and analyze the species.
Answer: option D
The sodium potassium ion exchange move sodium and potassium in opposite direction in electrochemical gradients.
Explanation:
The sodium potassium pump is found in many animals plasma membranes and its moves the sodium and potassium ion in opposite direction across the plasma membrane with the hydrolysis of ATP(adenosine triphosphate) to supply the needed energy. It is an active transport process.
the Nucleus
Explanation:
Known as the cell's “command center,” the nucleus is a large organelle that stores the cell's DNA (deoxyribonucleic acid). The nucleus controls all of the cell's activities, such as growth and metabolism, using the DNA's genetic information.
The volume is mass density is h,w,l
I'm not completely sure, but I'm fairly certain that the answer is B.