Question

Read the following four statements carefully.
i. Ventral respiratory group of neurons of medulla oblongata can cause both inspiration and expiration.
ii. The part of the respiratory system starting with the external nostrils up to the terminal bronchioles constitutes the respiratory or exchange part of the respiratory system.
iii. During swallowing epiglottis can be covered by a thin elastic cartilaginous flap called glottis to prevent the entry of food into the larynx.
iv. Binding of oxygen with haemoglobin is primarily related to partial pressure of ${O_2}$.
Which of the above two statements are correct?

a. (ii) and (iii)
b. (iii) and (iv)
c. (i) and (ii)
d. (i) and (iv)

Answer 1

Hint: The respiratory center is situated in the medulla oblongata and pons, in the brainstem which is in the rear mind before the medulla and pons. The respiratory center consists of three significant respiratory gatherings of neurons, two in the medulla, and one in the pons.

Complete answer:
> The aspect of the respiratory framework beginning with the outside nostrils up to the terminal bronchioles establishes the directing part while the alveoli and their conduits structure the respiratory or trade part. During gulping, glottis can be secured by a meager versatile cartilaginous fold called epiglottis to forestall the section of food into the larynx. The VRG contains both inspiratory and expiratory neurons The ventral respiratory gathering of neurons are dynamic in powerful breathing and dormant during calm, serene breaths. The VRG sends inhibitory driving forces to the apneustic focus. So, option (i) is correct.

> Practically, the respiratory framework is isolated into a directing zone and respiratory zone. The leading zone comprises the nose, pharynx, larynx, windpipe, bronchi, and bronchioles. So, option (ii) is incorrect.

> Every hemoglobin particle can convey a limit of four atoms of oxygen. The authoritative oxygen with hemoglobin is fundamentally identified with the incomplete weight of oxygen. The incomplete weight of carbon dioxide, hydrogen particle focus (pH), and temperature are different elements, which can influence this official. So, option (iv) is correct.

> During gulping, glottis can be secured by a meager versatile cartilaginous fold called epiglottis to forestall the section of food into the larynx. So, option (iii) is incorrect.

Hence, Option (D), which is (i) and (iv) is the correct answer.

Note: The respiratory center is liable for producing and keeping up the beat of breath, and furthermore of altering this in homeostatic reaction to physiological changes. The respiratory focus gets contribution from chemoreceptors, mechanoreceptors, the cerebral cortex, and the nerve center so as to direct the rate and profundity of relaxing. Information is animated by modified degrees of oxygen, carbon dioxide, and blood pH, by hormonal changes identifying with pressure and nervousness from the nerve center, and furthermore by signals from the cerebral cortex to give a cognizant control of breath.