sebaceous follicle

follicle

[fol´ĭ-k'l] a sac or pouchlike depression or cavity. adj., adj follic´ular.atretic ovarian follicle an involuted ovarian follicle.dental follicle the structure within the substance of the jaws enclosing a tooth before its eruption; the dental sac and its contents.gastric f's lymphoid masses in the gastric mucosa.graafian follicle see graafian follicle.hair follicle one of the tubular invaginations of the epidermis enclosing the hairs, and from which the hairs grow.

Diagram of a hair follicle showing layers of hair schematically. From Copstead, 1995.lymph follicle (lymphatic follicle) 1. lymph node.2. lymphatic nodule (def. 2).Naboth's f's (nabothian f's) Naboth's cysts.ovarian follicle the ovum and its encasing cells, at any stage of its development.primary ovarian follicle an immature ovarian follicle consisting of an immature ovum and the few specialized epithelial cells surrounding it.primordial ovarian follicle an ovarian follicle consisting of an ovum enclosed by a single layer of cells.sebaceous follicle a hair follicle with a relatively large sebaceous gland, producing a relatively insignificant hair.solitary f's 1. areas of concentrated lymphatic tissue in the mucosa of the colon.2. small lymph follicles scattered throughout the mucosa and submucosa of the small intestine. Called also solitary glands.thyroid f's discrete cystlike units filled with a colloid substance rich in iodine; they constitute the lobules of the thyroid gland.vesicular ovarian follicle graafian follicle.

follicle

(fol'i-kl) [L. folliculus, little bag] A small secretory sac or cavity. follicular, adjective

atretic follicle

An ovarian follicle that has undergone degeneration or involution.

dental follicle

1. The connective tissue structure that encloses the developing tooth within the substance of the jaw before tooth eruption.2. The dental sac and its contents.

gastric follicle

The glands in the gastric mucosa of the stomach.

graafian follicle

See: graafian follicle

hair follicle

An invagination of the epidermis that forms a cylindrical depression, penetrating the corium into the connective tissue that holds the hair root. Sebaceous glands, which secrete sebum, and tiny muscles (arrectores pili), which cause the hair to stand, are attached to these follicles.

lymphoid follicle

A densely-packed, spherical or ovoid aggregation of B lymphocytes that forms a lymphocyte proliferation and maturating zone in a lymphoid tissue, such as a lymph node. Synonym: lymph follicle

maturing follicle

See: graafian follicle

nabothian follicle

A dilated cyst of the glands of the cervix uteri.

ovarian follicle

A spherical structure in the cortex of the ovary consisting of an oogonium or an oocyte and its surrounding epithelial (follicular) cells. The follicles are of three types. The first type, or primary follicle, consists of an oogonium and a single layer of follicular cells. In the second type, or growing follicle, cells proliferate, forming several layers, and the first maturation division occurs. The third type, the vesicular (graafian) follicle, possesses a cavity (antrum) containing the follicular fluid (liquor folliculi). The oocyte lies in the cumulus oophorus, a mass of cells on the inner surface. The cells lining the follicle constitute the stratum granulosum. The follicle is a secretory structure producing estrogen and progesterone. See: corpus luteum

primordial follicle

An ovarian follicle consisting of the ovum enclosed in a single layer of cells.