PADI Divemaster Certification Practice Exam

At what rate do body tissues absorb and release nitrogen while diving?

1. Uniformly across all tissues

2. At different rates based on blood flow and solubility

3. More quickly in higher temperatures

4. More quickly in higher altitudes

The correct answer is: At different rates based on blood flow and solubility

Body tissues absorb and release nitrogen at different rates based on factors like blood flow and the solubility of nitrogen in those tissues. Tissues that have a high blood flow, such as the brain and lungs, tend to absorb and release nitrogen more rapidly than those with lower blood flow, such as fat tissues. Additionally, the solubility of nitrogen varies among different types of tissues; for instance, nitrogen is more soluble in fatty tissues than in muscle. This results in a complex interaction where each tissue type will exchange nitrogen differently during both the ascent and descent phases of a dive. Therefore, understanding the varying rates at which nitrogen is absorbed and released is crucial for managing decompression and preventing decompression sickness. In contrast, the other options do not accurately represent the dynamics of nitrogen absorption and release in the body. Uniform absorption would not account for the varying physiological conditions that influence how quickly nitrogen is taken up or released. Higher temperatures do affect diving physiology but primarily influence the rate of metabolism rather than directly changing the absorption rate of nitrogen. Similarly, while altitude does affect gas solubility, it does not apply directly to nitrogen absorption behavior during diving but rather relates to ascent and dive planning.