Question

The tiny air sacs present in the human lungs are called as

• A. Bronchioles
• B. Trachea
• C. Larynx
• D. Alveoli

Hint:

Alveoli = Air sacs. This is where the "business" of breathing happens.

Answer 1

The Correct Option is D

Step 1: Concept
The respiratory system consists of a series of tubes that end in specialized structures for gas exchange.

Step 2: Meaning
Gas exchange requires a massive surface area and very thin membranes for oxygen and carbon dioxide to pass through.

Step 3: Analysis
The Trachea and Larynx are part of the upper airway, and Bronchioles are small tubes. The Alveoli are the microscopic, grape-like air sacs where the actual exchange of gases with the blood occurs.

Step 4: Conclusion
Alveoli are the functional units of the lungs where gas exchange takes place.

Final Answer: (D)