Question

Which of the following statements is correct?
A. During inspiration external intercostal muscles and diaphragm contract.
B. Cyanosis means collapse of alveoli.
C. Eupnea is slow breathing.
D. Coryza is caused by human coronavirus.

Answer 1

Breathing and respiration are two distinct but linked physiological processes that aid in the correct functioning of body organs. Breathing is a physical process of exchanging gases, whereas respiration is a chemical activity that creates energy at the cellular level. Respiratory tract along with the passage for air is also the portal for the entry of pathogens.

Complete answer:
Option: A – The diaphragm and external intercostal muscles contract during inspiration to allow air to enter the lungs, which necessitates the contraction of numerous muscles; the diaphragm and external intercostal muscles contract.
Thus, Option A is correct.
Option: B - Cyanosis is a disease that causes the skin, nails, lips, and area around the eyes to turn a bluish or greyish colour. Thus, the statement in the option is a wrong fact.
Thus, Option B is not correct.
Option: C - Eupnea is a term used to describe normal, healthy, unlabored breathing in mammals. It is also known as silent breathing or resting respiratory rate. Expiration in eupneas relies only on the lungs' elastic recoil. All animals, including humans, breathe naturally through eupnea. Thus, the statement in the option is a wrong fact.
Thus, Option C is not correct.
Option: D – Coryza is also known as a common cold which is caused by Rhinovirus and is not caused by human coronavirus.
Thus, Option D is also not correct.

Hence, Option A) During inspiration external intercostal muscles and diaphragm contract is the correct answer.

Note:
We breathe by inhaling through our nose and exhaling through our mouth. Inhalation is the process of bringing oxygen-rich air into the body and expiration is the process of removing carbon dioxide-rich air from the body. Both of these processes occur on a regular basis during breathing. As a result, a breath is defined as "one inhale, one exhale."