Which of the following is the primary site for the exchange of inhaled air in the human respiratory system?

Name the final product$(s)$ obtained in anaerobic respiration if it takes place in a plant (like yeast).

In the following questions, a statement of Assertion $(A)$ is followed by a corresponding statement of Reason $(R)$. Mark the correct answer as:
Assertion $(A)$: Exchange of oxygen and carbon dioxide occurs between blood vessels and alveoli.
Reason $(R)$: Oxygen diffuses from alveoli to blood vessels and carbon dioxide diffuses from blood vessels to alveoli.

Which of the following statements is (are) correct?
$(i)$ Pyruvate can be converted into ethanol and carbon dioxide by yeast.
$(ii)$ Fermentation takes place in aerobic bacteria.
$(iii)$ Fermentation takes place in mitochondria.
$(iv)$ Fermentation is a form of anaerobic respiration.

Describe the events that occur during the process of breathing in humans.

Differentiate between the left lung and the right lung of humans.