What are structures that produce secretions known as?

Glands are specialized structures in the body that produce and release secretions. These secretions can include hormones, enzymes, or other fluids that play essential roles in various physiological processes. Glands can be classified into different types, such as exocrine glands, which secrete substances onto epithelial surfaces through ducts (like sweat glands and salivary glands), and endocrine glands, which release hormones directly into the bloodstream (like the thyroid gland and adrenal glands).

Understanding the role of glands is crucial in comprehending how different systems in the body function, as their secretions often regulate metabolism, growth, and other vital processes. Other choices, such as cells, muscles, and tissues, refer to broader biological components and do not specifically denote structures designated for secretion, making them less accurate in this context.