Integumentit

Integumentit, in English typically referred to as integuments, are the outer coverings that surround and protect an organism. In animals, the integument includes the skin and its derivatives—epidermis, dermis, hair or fur, nails, scales, feathers, glands, and the associated sensory structures. The integumentary system as a whole serves as a protective barrier, reduces water loss, defends against mechanical injury, aids in thermoregulation, and contributes to coloration and communication. Its development involves embryonic tissues, with the epidermis usually arising from ectoderm and the underlying dermis from mesoderm in vertebrates. In many lineages the integument also becomes specialized, such as keratinized hair, scales, feathers, or shells.

In botany, the term integument refers to the protective envelope surrounding the ovule. Most seed plants have one or two integuments that encase the nucellus; after fertilization these layers contribute to the seed coat. The micropyle is the opening through which the pollen tube enters during fertilization. The number and structure of integuments vary among taxa, with some species exhibiting a single integument and others a double integument. The integument thus plays a crucial role in protecting the developing embryo and regulating seed development, dormancy, and dispersal.

Etymology wise, the term derives from Latin integumentum, meaning clothing or covering. In evolutionary terms, integumentary structures such as skin, scales, feathers, and seed coats have been central to major adaptations across plants and animals.