glandes

In biology, a gland is an organ that synthesizes and secretes substances for use elsewhere in the body or for elimination. The term gland comes from Latin glandula; in French, glands are called glandes, with the plural glandes. Glands can be multicellular and highly organized or unicellular, as goblet cells, embedded in the epithelium.

Glands are commonly classified by their mode of secretion: endocrine glands release hormones into the bloodstream, while exocrine glands secrete through ducts onto surfaces or into body cavities. A third category includes mixed glands that perform both roles, such as the pancreas. Structurally, glands may be tubular, acinar (alveolar), or tubuloalveolar, and secretions can be merocrine, apocrine, or holocrine.

Endocrine glands regulate physiology by hormones, coordinating metabolism, growth, reproduction, and homeostasis. Notable endocrine glands include the pituitary, thyroid, parathyroid, adrenal, and pineal glands, as well as the endocrine pancreas and gonads. Exocrine glands secrete enzymes, mucus, or other substances onto epithelia or into the gastrointestinal tract; examples include salivary glands, lacrimal glands, gastric glands, pancreatic acini, the biliary system, sweat glands, and sebaceous glands.

Disorders involve hypersecretion or hyposecretion, leading to diseases such as diabetes mellitus, hypothyroidism, hyperthyroidism, or exocrine pancreatic insufficiency; autoimmune conditions like Sjögren's syndrome; and various glandular tumors.