Question

Chemosensitive area of respiratory centre in medulla is affected by.
A. Less $C{O_2}$ and H ions
B. less ${O_2}$ and H ions
C. excess $C{O_2}$ and H ions
D. Excess ${O_2}$ and H ions.

Answer 1

Hint: Chemosensitive area of respiratory center is the specialized centre present in the medulla part of the brain that is known as respiratory rhythm centre, which is mainly responsible for regulation. This is influenced by the concentration of $C{O_2}$ and Hydrogen ions.

Complete answer:
The ability of maintaining the respiratory rhythm according to demand of the body tissue. Which is controlled by the medulla region of the brain, basically the respiratory center lies in the medulla oblongata and pons varolii of the brain. This respiratory center takes input from the chemoreceptor, mechanoreceptors, cerebral cortex and the hypothalamus, to maintain the regulation of rate and depth of breathing, oxygen, carbon dioxide and blood pH, altered levels stimulate the such inputs. Injury to such a respiratory group leads to breathing disorder. The respiratory center is divided into 3 main groups, two in medulla that are known as dorsal and ventral respiratory group, in pons, the pontine respiratory group.
A chemo-sensitive area lies just to the rhythm center which is highly sensitive to change in the concentration of carbon dioxide and hydrogen ions in the blood, so an increase in the concentration of carbon dioxide and hydrogen ions stimulates the center which further makes it maintain the homeostasis of respiratory rhythm. The respiratory center starts the expiration process instead of inspiration.

Note: The respiratory depression is caused by the brain trauma, brain damage, brain tumor, drugs (opioids and sedatives). Faster and deeper breaths are stimulated by the amphetamine which stimulate the respiratory center. Breathing of air, in or out from the lungs are in control of autonomic nervous systems. There are three phases in the respiratory cycle such as inspiration, post- inspiration or active inspiration.