Question

Which is the correct sequence of air passage during inhalation?

• A. Nostrils → Larynx → Pharynx → Trachea → Lungs
• B. Nasal passage → Trachea → Pharynx → Larynx → Alveoli
• C. Larynx → Nostrils → Pharynx → Lungs
• D. Nostrils → Pharynx → Larynx → Trachea → Alveoli

Answer 1

The correct option is D

Nostrils → Pharynx → Larynx → Trachea → Alveoli

The correct option is D.

Explanation for the correct option:

Option D:

1. During inhalation, air enters via the nose or mouth and travels down the pharynx towards the pharynx.
2. It enters the windpipe. The trachea is divided into two air passages known as the bronchial tubes. Each bronchial tube leads to a lung.
3. These tubes then divide into smaller bronchi and then branch into bronchioles.
4. The bronchioles lead to small air sacs called alveoli. These are the sites of oxygen transfer.

Explanation for incorrect answer:

Option A:

The air enters via the nose and travels down the pharynx into the larynx and then into the windpipe.

Option B:

1. The air enters via the nose and travels down the pharynx into the larynx and then into the windpipe.
2. The trachea then opens into the bronchial tubes.

Option C:

1. The air enters via the nostrils and travels down the pharynx into the larynx and then into the windpipe.
2. The trachea then opens into the bronchial tubes.

Final answer: The correct sequence of air passage during inhalation is Nostrils → Pharynx → Larynx → Trachea → Alveoli.