Follicle

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Related to atretic follicle: corpus albicans, secondary follicle

follicle

[′fäl·ə·kəl]
(biology)
A deep, narrow sheath or a small cavity.
(botany)
A type of dehiscent fruit composed of one carpel opening along a single suture.

Follicle

 

a dry, one-celled, many-seeded, and monocarpel-lary fruit that opens along a ventral suture. The seeds are located along the suture on the edges of the carpel. Follicles are typical of the magnolias; of such members of Ranunculaceae as cowslip, garden columbine, aconite and larkspur; and of some genera of Rosaceae, such as Physocarpus.

The simplest follicles resemble a leaf folded in half lengthwise; the upper part corresponds to a stigma and the stem to a stalk. A large number of follicles may be positioned in a spiral on the axis of a blossom (as in the magnolia) to form a multiple fruit. Other types of fruits developed from follicles: nuts are follicles with a single seed, and beans are follicles with a different form of opening.


Follicle

 

a round, oval, or pear-shaped anatomical structure present in various organs in man and other vertebrates, having varied functions. In mammals egg cells develop within the ovarian follicle, which consists of a group of cells; one of these is the egg cell and the rest are epithelial cells surrounding the egg, first in one layer and then in several. As the follicle matures, spaces between the cells become filled with a clear liquid, and the single-layered primordial follicle is transformed into a mature multi-layered follicle, the Graafian follicle.

The follicle of the thyroid gland secretes thyroglobulin, a precursor of the thyroid hormones. Into the hair follicles, which enclose the hair roots and bulbs, empty excretory ducts of the sebaceous glands. Many lymphatic follicles are located in the mucous membranes of the digestive tract, the respiratory tract, and the urinary tract; for instance, follicles known as peyer’s patches are situated in the mucous membrane layer of the intestine.

References in periodicals archive ?
In the animals undergoing BUAL, the cortex of ovaries was covered with small antral atretic follicles (<100-200 [micro]m).
In the present study we also showed that melatonin treatment causes an increase in the number of antral follicles and a decrease in the number of atretic follicles, suggesting that melatonin may inhibit follicular atresia.
While maintaining the balance, it has shown promising results in preserving the number of primordial, primary and secondary follicles; however, it has not been able to reduce the number of atretic follicles within CYP exposed ovaries.
According to HE staining of slices of the right ovary, it was found that the ovarian tissue was destroyed and there were few structurally complete follicles and abundant atretic follicles in the 0 mg/kg curcumin group compared to the normal control [Figure 1];[Table 3].
One way ANOVA test showed the difference was statistically significant when mean value of diameter of atretic follicles of groups A, B, C, D and E was compared among one another, the p-value was < 0.001*.
A mean of 317.8 [+ or -] 30.9 of both functional and atretic follicles for the control group and 352.2 [+ or -] 44.7 follicles for the hypothyroid group were counted.
The number of atretic follicles and severity of productive processes in them decreased too.
Expression of ski in the granulosa cells of atretic follicles in the rat ovary.
The presence of retained yolk material, presumed to be postovulatory follicles or atretic follicles, was evaluated in the 18 female Puerto Rican parrots.
Developing follicles, atretic follicles and corpus luteum lie in the stroma of cortex.
Macrophages cluster around atretic follicles and are involved in their clean up of the atretic follicles.