Integument
In biology, integument is the natural covering of an organism or an organ, such as its skin, husk, shell, or rind. It derives from "integumentum", which is Latin for "a covering". In a transferred or figurative sense, it could mean a cloak or a disguise. In English "integument" is a fairly modern word, its origin having been traced back to the early seventeenth century. It can mean a material or layer with which anything is enclosed, clothed, or covered in the sense of "clad" or "coated", as with a skin or husk. Botanical usage. In botany the senses are  similar to those in zoology, referring to the covering of an organ. When the context indicates nothing to the contrary, the word commonly refers to an envelope covering the ovule. The integument may consist of one layer (unitegmic) or two layers (bitegmic), each of which consisting of two or more layers of cells. The integument is perforated by a pore, the micropyle, through which the pollen tube can enter. It may develop into the testa, or seed coat. Zoological usage. The integument of an organ in zoology typically would comprise membranes of connective tissue such as those around a kidney  or liver. In referring to the integument of an animal, the usual sense is its skin and its derivatives: the integumentary system, where "integumentary" is a synonym for "cutaneous". In arthropods, the integument, or external "skin", consists of a single layer of epithelial ectoderm from which arises the cuticle, an outer covering of chitin the rigidity of which varies as per its chemical composition.It is present in ovule and also work in it with nucelleus. Derivative terms and sundry usages. Derivative terms include various adjectival forms such as integumentary (e.g. system), integumental (e.g. integumental glands, "peltate glands, the integument  being raised like a bladder due to abundant secretion") and integumented (as opposed to bare). Other illustrative examples of usage occur in the following articles: