Name the process by which plant parts like roots, stems, and leaves get oxygen required for respiration.

The mechanism of the human body which facilitates the exchange of respiratory gases is called:

Name the substance which is oxidised in the body during respiration.

In the following questions, a statement of Assertion is given followed by a corresponding statement of Reason. Mark the correct answer as:
Assertion: During inhalation, the diaphragm flattens and increases the chest cavity.
Reason: Due to this, air enters the lungs.

The surface across which breathing in animals occurs is very fine and delicate. How do organisms protect such surfaces within their body?

If one holds their breath after expiration for about $30 \text{ s}$, would there still be any exchange of respiratory gases in the lungs during this period? Explain.