To prevent blood flowing back after each heartbeat. They ensure that the blood flows only in one direction (back to the heart).
Definite volume is doesn’t possess a definite volume so therefore the answer is c
Answer:
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Explanation:
All of the body processes, like digestion, pumping blood, breathing, are powered by cells converting the stored chemical energy into work and heat, in a process called respiration. ... Inside the muscle cells of the human (or any animal), the chemical energy is transformed (changed) into mechanical work and heat.
The cytoplasm is divided by cytokinesis
