Question

Which of the following is the incorrect statement for respiration in humans?

• A. Neural signals from pneumotaxic centre in pons region of brain can increase the respiratory rate
• B. About $90\%$ of carbon dioxide $\left(C{O}_2\right)$ is carried by haemoglobin as carbamino haemoglobin
• C. Workers in grinding and stone-breaking industries may suffer from lung fibrosis
• D. Cigarette smoking may lead to inflammation of bronchi

Answer 1

The correct option is B About $90\%$ of carbon dioxide $\left(C{O}_2\right)$ is carried by haemoglobin as carbamino haemoglobin

• Cigarette smoke is itself an inflammatory mediator and induces pulmonary inflammation by damaging the respiratory epithelial barrier.
• Neural signal from this centre can reduce the duration of inspiration and thereby alter the respiratory rate.
• Pulmonary fibrosis is a lung disease that occurs when lung tissue becomes damaged and scarred.
• Around $72\%$ of the carbon dioxide is carried in the form of bicarbonate ions in the plasma. $21\%$ of the carbon dioxide in the form carbamino haemoglobin (carbon dioxide combined with haemoglobin). Around $7\%$ carbon dioxide is dissolved in plasma.

So, the correct answer is- option d.