Question

Which one of the following is the correct statement for respiration in humans?

• A. Cigarette smoking may lead to inflammation of bronchi
• B. Neural signals from pneumotoxic centre in pons region of brain can increase the duration of inspiration
• C. Workers in grinding and stone-breaking industries may suffer, from lung fibrosis
• D. About $90\%$ of carbon dioxide $(CO_2)$ is carried by haemoglobin as carbamino- haemoglobin

Answer 1

Answer: (C)

Workers in grinding and stone-breaking industries may suffer, from lung fibrosis

Answer 2

In certain industries, especially those involving grinding or stone breaking so much dust is produced that the defense mechanism of the body cannot fully cope with the situation. Long exposure can give rise to inflammation leading to fibrosis (proliferation of fibrous tissues) and thus causing serious lung damage. Workers in such industries should wear protective masks.