Answer:
if anaerobic activity takes place over a long period of time the muscles soon become exhausted
Answer:
What sends oxygenated blood back to the heart from the lungs?
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
Explanation:
It is used by every living cell.
Cellular respiration is a process of combining oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining activities and discarding, as waste products, carbon dioxide and water.
Answer:
D
Explanation:
Most of the energy in the United States comes from the burning of fossil fuels (coal, oil, natural gas). Hope this helps!