Question

Identify the correct sequence of the air passage in man:

• A. External Nares → Nasal chamber → Trachea → Pharynx → Bronchi → Bronchioles → Alveoli
• B. External Nares → Nasal chamber → Pharynx → Larynx → Bronchi → Trachea → Bronchioles → Alveoli
• C. External Nares → Nasal chamber → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli
• D. External Nares → Nasal chamber → Pharynx → Larynx → Trachea → Bronchioles → Bronchi → Alveoli

Hint:

Remember: Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli

Answer 1

The Correct Option is C

The correct sequence of the air passage in humans is: \[ \text{External Nares} \rightarrow \text{Nasal chamber} \rightarrow \text{Pharynx} \rightarrow \text{Larynx} \rightarrow \text{Trachea} \rightarrow \text{Bronchi} \rightarrow \text{Bronchioles} \rightarrow \text{Alveoli} \] - External nares are the nostrils through which air enters.
- The nasal chamber warms and filters the air.
- Air then moves to the pharynx and passes through the larynx (voice box).
- From the larynx, it flows into the trachea (windpipe).
- The trachea divides into bronchi, which further divide into bronchioles.
- Finally, air reaches the alveoli where gaseous exchange occurs.

Answer 2

The respiratory system in humans is designed to efficiently transport air from the external environment to the sites of gas exchange in the lungs. The sequence of air passage ensures that the air is filtered, warmed, and humidified before reaching the delicate alveoli where oxygen and carbon dioxide exchange occurs.

Air enters through the external nares (nostrils), which allow the inhalation of air from the environment. From there, air passes into the nasal chamber, where it is filtered by hairs and mucus, warmed by blood vessels, and humidified to protect the respiratory tract.

Next, the air moves into the pharynx, a muscular tube that serves as a pathway for both air and food. The air then passes through the larynx, also known as the voice box, which houses the vocal cords and prevents food from entering the lower respiratory tract.

From the larynx, air travels down the trachea, a rigid tube supported by cartilage rings that keep the airway open. The trachea branches into two bronchi, each leading to one lung.

Inside the lungs, the bronchi further divide into smaller bronchioles, which spread throughout the lung tissue. Finally, air reaches the alveoli, tiny sac-like structures where gas exchange with the blood takes place.

Hence, the correct sequence of the air passage in man is:
External Nares → Nasal chamber → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli