Alaska Certified Nursing Assistant (CNA) Practice Exam 2025 - Free CNA Practice Questions and Study Guide

Hormones are indeed chemicals produced by various glands in the body that play a crucial role in regulating a wide array of bodily functions. They act as signaling molecules that travel through the bloodstream to target organs and tissues, influencing processes such as metabolism, growth and development, mood regulation, and reproductive functions. This intricate system of communication ensures that the body maintains homeostasis and responds appropriately to changes both internally and externally.

The other options describe different biological substances or functions. For example, substances that initiate the immune response fall under the category of cytokines or antibodies, which have a specific role in immune defense. Proteins responsible for muscle growth pertain to hormones like insulin and growth hormone, but they are not classified solely as hormones themselves. Minerals necessary for bone health, such as calcium and phosphorus, are essential nutrients but do not fit the definition of hormones. Thus, the answer highlights the primary function and nature of hormones accurately.