Answer:
Add them!
Explanation:
The mass number of an atom is its total number of protons and neutrons
Answer: Membrane transport proteins are specific and selective for the molecules they move, and they often use energy to catalyze passage. Also, these proteins transport some nutrients against the concentration gradient, which requires additional energy.
Explanation:
The flow of energy starts in in you arms. You put your hands together, and use your arms to move your hands back and forth, this is kinetic energy. Your hands rubbing together causes the molecules to bump into each other, this is friction. As the molecules bump into each other they begin to move faster, and the fast movements of the molecules is what creates heat.
Answer:
I think the correct answer is D
