Glandless

Glandless is an adjective used in biology to describe organisms, tissues, or cells that lack glands. Glands are secretory tissues or organs that produce and release substances such as hormones, enzymes, mucus, resins, essential oils, or pheromones.

In anatomy and pathology, glandless describes tissues or tumors that do not show glandular differentiation. For example, some carcinomas are described as glandless because they do not form glands, in contrast to gland-forming cancers such as adenocarcinomas. The term can also refer more generally to normal tissues that lack secretory structures. The use of glandless versus gland-forming is one way pathologists categorize tumor morphology and behavior.

In botany and plant sciences, glandless refers to tissues that lack secretory glands or glandular structures. Plants often possess glandular trichomes, resin ducts, or nectar glands, and glandless variants are those in which these secretory features are absent. The absence of glands can influence characteristics such as fragrance, defense against herbivores, and interactions with pollinators or microbes.

The concept of glandlessness is relative and context-dependent, varying by organism and tissue type. It is used in comparative anatomy, taxonomy, pathology, and plant physiology to describe the presence or absence of secretory capabilities. Related terms include glandular and nonglandular, as well as endocrine and exocrine classifications in animals.