Fill in the blanks:
a. Exhaled air has more ___ and less ___ in it than
inhaled air.
b. Oxygen is used for ___ of food.
c. The number of times air is inhaled or exhaled in a minute is called ___
d. Oxygen diffuses from air is the ___ to the blood in capillaries in the lungs.
e. Oxygen combines with haemoglobin to form ___​