Respiratory System Anatomy and Function

Steps:

• Evaluate option A: Goblet cells produce mucus, but they are in the bronchi, not alveoli.
• Evaluate option B: Cartilage provides structural support in bronchi to maintain openness.
• Evaluate option C: Bronchioles lack complete cartilage rings; they have smooth muscle.
• Evaluate option D: Bronchi have muscles that constrict/dilate, but alveoli do not; relaxation aids flow in airways.

Why B is correct:

• Bronchi contain C-shaped cartilage rings that prevent collapse, ensuring unobstructed airflow as per respiratory anatomy definitions.

Why the others are wrong:

• A: Goblet cells are in bronchi and trachea, not alveoli, which lack mucus production.
• C: Bronchioles have no cartilage rings; only bronchi do, allowing flexibility.
• D: Alveoli have no muscles; bronchial muscles relax during exercise for airflow, but alveoli do not.

Final answer: B