Exams › NEET › Biology

When you hold your breath, which of the following gas changes in blood would first lead to the urge to breathe?

1. rising CO2 concentration
2. falling CO2 concentration
3. rising CO2 and falling O2 concentration
4. falling O2 concentration

Correct answer: rising CO2 concentration

Solution

During breath-holding, carbon dioxide builds up in the blood quickly because it is continuously produced by metabolism. Central chemoreceptors are especially sensitive to this rise, which triggers the urge to breathe before oxygen falls enough to be the main stimulus.

Related NEET Biology questions

• Skin is an accessory organ of respiration in
• Name the pulmonary disease in which alveolar surface area involved in gas exchange is drastically reduced due to damage in the alveolar walls.
• Name the chronic respiratory disorder caused mainly by cigarette smoking.
• Which of the following are the correct statement for respiration in human?
• Blood analysis of a patient reveals an unusually high quantity of carboxyhaemoglobin content. Which of the following conclusions is most likely to be correct? The patient has been inhaling polluted air containing unusually high content of
• Reduction in pH of blood will

⚔️ Practice NEET Biology free + battle 1v1 →