The circulatory system<span> comprises the </span>heart<span>, veins, capillaries and arteries. ... Once depleted of oxygen, the blood returns to the lungs and </span>heart<span>. To </span>maintain homeostasis<span>, the </span>circulatory system<span> delivers oxygen and nutrients in the blood so that they can pass into fluids surrounding the cells.</span>
Gonads denotes the biological differences
Answer:
If I’m correct it’s O cosmic background radiation
Explanation:
She discovered that folate was crucial to sperm development. <span>It has been found that folate may have been the driving force behind the evolution of darker skin, factors such as clothing and climate affect the evolution of skin pigment. </span>
