Question

Lungs are spongy in nature due to the presence of tiny balloon-like structures called ________ .

• A. diaphragm
• B. chest cavity
• C. stomach
• D. abdominal cavity

Answer 1

The correct option is B

chest cavity

Both the lungs in humans are filled with tiny balloon-like structures called air sacs or alveoli. Their membrane is highly thin and is surrounded by many capillaries. Alveoli are the actual sites where gaseous exchange takes place between the air in the lungs and blood. Due to the presence of the air filled sacs, lungs are spongy in nature. Filtering units are present in the kidney and neurons are nerve cells which conduct electric signals.