ovarian follicle
Quick Summary
An ovarian follicle is a small, fluid-filled sac within the ovary that contains a developing egg cell, or ovum. These follicles are crucial for female reproduction, housing the ova from birth until they mature and are released during ovulation.12345
Ovarian Follicle Development
- Primordial Follicles: At birth, a female has hundreds of thousands of these undeveloped follicles, each containing a primary ovum.31
- Maturation: Stimulated by hormones like follicle-stimulating hormone (FSH) from the pituitary gland, a follicle matures over about four months.465
- Ovulation: When mature, the follicle ruptures, releasing the ovum from the ovary. This process is called ovulation and typically occurs once per menstrual cycle.4
If the ovum is not fertilized within 24 hours of ovulation, it degenerates. The remaining follicular cells form the corpus luteum, which secretes hormones to prepare the uterus for potential pregnancy.45
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human reproductive systemOvarian structureThe ovarian follicles, sometimes called graafian follicles, are rounded enclosures for the developing ova in the cortex near the surface of the ovary. At birth and in childhood they are present as numerous primary or undeveloped ovarian follicles. Each contains a primitive ovum, or oocyte, and…
Read MoreThe ovarian follicles, sometimes called graafian follicles, are rounded enclosures for the developing ova in the cortex near the surface of the ovary. At birth and in childhood they are present as numerous primary or undeveloped ovarian follicles. Each contains a primitive ovum, or oocyte, and…
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menstruationBiological significance…hormones that induce ripening of ovarian follicles—ova and the cellular structures that enclose them. These pituitary hormones, called gonadotropic hormones, are carried to the ovaries by way of the bloodstream. In primates the hypothalamic mechanism normally is independent of external stimuli, and regular discharge of ova into the tubes leading…
Read More…hormones that induce ripening of ovarian follicles—ova and the cellular structures that enclose them. These pituitary hormones, called gonadotropic hormones, are carried to the ovaries by way of the bloodstream. In primates the hypothalamic mechanism normally is independent of external stimuli, and regular discharge of ova into the tubes leading…
Read More
hormoneFollicle-stimulating hormoneFSH stimulates development of the graafian follicle, a small vesicle containing an egg, in the ovary of the female mammal. In the male it promotes the development of the tubules of the testes and the differentiation of sperm. FSH, like thyrotropin, is a glycoprotein, with an estimated molecular weight (in…
Read MoreFSH stimulates development of the graafian follicle, a small vesicle containing an egg, in the ovary of the female mammal. In the male it promotes the development of the tubules of the testes and the differentiation of sperm. FSH, like thyrotropin, is a glycoprotein, with an estimated molecular weight (in…
Read More- hormoneEstrogens
…the mammalian ovary by the ovarian follicle, or vesicle, including the granulosa cells immediately surrounding the ovum, or egg, and the cells of the theca, which forms a supporting outer wall for the follicle. The main estrogen secreted is called β-estradiol. The close relationship between the female and the male…
Read More…the mammalian ovary by the ovarian follicle, or vesicle, including the granulosa cells immediately surrounding the ovum, or egg, and the cells of the theca, which forms a supporting outer wall for the follicle. The main estrogen secreted is called β-estradiol. The close relationship between the female and the male…
Read More - follicle-stimulating hormone
…(LH), stimulates development of the graafian follicle, a small, egg-containing vesicle in the ovary of the female mammal; in the male, it promotes the development of the tubules of the testes and the differentiation of sperm. Though in the male the presence of FSH is necessary for the maturation of…
Read More…(LH), stimulates development of the graafian follicle, a small, egg-containing vesicle in the ovary of the female mammal; in the male, it promotes the development of the tubules of the testes and the differentiation of sperm. Though in the male the presence of FSH is necessary for the maturation of…
Read More - luteinizing hormone
…promotes the transformation of the graafian follicle (a small egg-containing vesicle in the ovary) into the corpus luteum, an endocrine gland that secretes progesterone. In the male, LH stimulates the development of the interstitial cells of the testes, which secrete testosterone, a male sex hormone. The production of LH is…
Read More…promotes the transformation of the graafian follicle (a small egg-containing vesicle in the ovary) into the corpus luteum, an endocrine gland that secretes progesterone. In the male, LH stimulates the development of the interstitial cells of the testes, which secrete testosterone, a male sex hormone. The production of LH is…
Read More