Which of the following statements is correct ?

Options

A. During inspiration external intercostal muscles and diaphragm contract.
B. Cyanosis mean collapse of alveoli.
C. Eupnea is slow breathing.
D. Coryza is caused by human coronavirus.

Explanation

To determine which statement is correct, we need to analyze each of the four statements provided:

1. **Statement 1**: "During inspiration, external intercostal muscles and diaphragm contract."
- **Analysis**: This statement is correct. During the process of inspiration (inhaling), the diaphragm contracts and moves downward, while the external intercostal muscles contract to lift the rib cage. This contraction increases the volume of the thoracic cavity, leading to a decrease in internal pressure compared to the atmospheric pressure, allowing air to flow into the lungs.

2. **Statement 2**: "Cyanosis means the collapse of wall."
- **Analysis**: This statement is incorrect. Cyanosis refers to a bluish discoloration of the skin due to insufficient oxygen in the blood, not the collapse of any structure.

3. **Statement 3**: "Eupnea is referred to as slow breathing."
- **Analysis**: This statement is incorrect. Eupnea refers to normal, unlabored breathing, not slow breathing. Slow breathing is termed "bradypnea."

4. **Statement 4**: "Chrysa is caused by human coronavirus."
- **Analysis**: This statement is incorrect. The term "chrysa" is not commonly associated with human coronavirus. The disease caused by the coronavirus is COVID-19.

Based on the analysis above, the correct statement is:

**Correct Answer**: During inspiration, external intercostal muscles and diaphragm contract.

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