NREMT Paramedic Practice

What is the normal range for pH levels in the human body?

1. 6.80-7.20

2. 7.35-7.45

3. 7.00-7.30

4. 7.50-7.70

The correct answer is: 7.35-7.45

The normal range for pH levels in the human body is from 7.35 to 7.45, which reflects the tight regulation of acid-base balance essential for physiological homeostasis. This range is crucial because even slight deviations can lead to significant physiological consequences, such as acidosis or alkalosis, affecting cellular functions and overall metabolism. Maintaining this pH range is vital for enzyme activity, electrical excitability of cells, and the transport of oxygen and carbon dioxide. The body employs multiple mechanisms, including respiratory and renal systems, to keep pH within this range by regulating carbon dioxide and bicarbonate levels. Other ranges mentioned in the options fall outside this normal physiological range, indicating pathological states rather than healthy body function. For example, a pH lower than 7.35 can indicate acidosis, while a pH higher than 7.45 can indicate alkalosis. Thus, understanding the normal pH range is essential for anyone involved in healthcare, as it helps in assessing and managing patients effectively.