Secretion is the process by which substances are produced and released from cells or glands in the body. This can include hormones, enzymes, and other important molecules that help regulate various bodily functions. For example, the pancreas secretes insulin, which helps control blood sugar levels. In addition to hormones, secretion also involves the release of fluids, such as saliva from the salivary glands or mucus from mucous membranes. These secretions play vital roles in digestion, protection, and lubrication, ensuring that the body operates smoothly and efficiently.