Advanced Placement (AP) Biology Practice Exam

The primary function of negative feedback in hormone regulation is to maintain hormone levels within a normal range. This mechanism operates by detecting changes in hormone concentrations and reversing those changes to stabilize the internal environment.

In negative feedback, when a certain hormone reaches a specific threshold level, the endocrine system senses this change. In response, it decreases the secretion of that hormone or its stimulating factors. For example, if a hormone's level gets too high, the body will initiate processes to lower its production, ensuring that levels do not exceed necessary limits. This is crucial for maintaining homeostasis, as it allows the body to adapt to fluctuations in hormone levels due to various factors, such as stress, diet, and activity levels.

This feedback loop helps prevent imbalances that can lead to disorders or diseases, such as hyperthyroidism or adrenal insufficiency, where hormone levels are maintained at either too high or too low:

- Increasing hormone production or enhancing the effects of hormones often leads to a state of imbalance rather than stability.

- Creating new hormones does not directly relate to the regulatory function of negative feedback but rather involves the synthesis processes of hormone production.

Thus, the role of negative feedback is critical for regulating and stabilizing hormone functions within the body, keeping them within a normal physiological