Aerobic atmosphere is maintained by_______

Oxygen balance in the atmosphere is maintained by a process called

The CO_2 concentration in the atmosphere is maintained normal by:

How is the balance of oxygen in atmospheric air maintained ?

True or false .If False , give the correct statement: The balance of oxygen in atmosphere is maintained through photosynthesis in animals and respiration in plants.

The presence of nitrogen in the atmosphere is maintained due to –

Pepsinogen is activated by_______.

Cardiac muscles are innervated by_______.