Explanation:
Excretion - Getting rid of
waste
Reproduction- The ability to
produce
offspring to
keep the
species in
existence.
Growth- The process
increasing
hysical
The Major function of the respiratory system is to exchange oxygen and carbon dioxide. Inhaled oxygen enters the lungs and reaches the alveoli, the layers of the cells lining the alveoli and the surrounding capillaries are each only one cell thick and are in very close contact with each other, the barrier between air and blood averages about 1 micron in thickness. Oxygen diffuses quickly through the air-blood barrier into the blood in the capillaries. Similarly, carbon dioxide passes from the blood into the alveoli and is then exhaled.
Sun is the source of energy for life on earth.
Answer Sun -d)
