Explanation:

When we take a long deep breath, it is known as inhalation or inspiration. During inhalation, the diaphragm and intercostal muscles contract, causing the chest cavity to expand. This expansion creates a negative pressure within the lungs, causing air to rush in. Oxygen (O2) from the inhaled air is then transported into the bloodstream, while carbon dioxide (CO2) is expelled from the body through exhalation.

Respiration and Breathing:

It is important to understand the difference between respiration and breathing. Respiration refers to the process by which oxygen is delivered to cells in the body and carbon dioxide is removed. It involves both inhalation and exhalation, as well as the exchange of gases in the lungs and at the cellular level. On the other hand, breathing specifically refers to the mechanical process of inhaling and exhaling air.

Changes in CO2 and O2 Levels:

During normal respiration, the level of CO2 in the blood increases, while the level of O2 decreases. This is because oxygen is continuously being used by the body's cells for various metabolic processes, and carbon dioxide is produced as a waste product. The CO2 is then transported back to the lungs through the bloodstream to be exhaled.

Effect of Deep Breath:

When we take a long deep breath, it increases the lung's capacity to hold air. This allows for a larger amount of oxygen to be inhaled and a greater amount of carbon dioxide to be exhaled. As a result, the level of CO2 in the blood decreases, while the level of O2 increases.

Pause in Respiration:

After taking a long deep breath, there is a brief pause in respiration. This is because the increase in O2 and decrease in CO2 levels in the blood trigger a temporary inhibition of the breathing reflex. The body recognizes that there is sufficient oxygen and less carbon dioxide present, so there is no immediate need to continue inhaling and exhaling.

Resumption of Respiration:

Eventually, the body's need for oxygen and the elimination of carbon dioxide will trigger the resumption of respiration. The breathing reflex will be stimulated again, and we will resume inhaling and exhaling.

Conclusion:

In conclusion, after taking a long deep breath, the pause in respiration is due to the decrease in CO2 levels in the blood. This temporary inhibition of the breathing reflex occurs because the body recognizes that there is sufficient oxygen and less carbon dioxide present.