Ovaries in the context of "Heterocrine gland"

A woman is an adult female human. Before adulthood, a female child or adolescent is referred to as a girl.

Typically, women inherit a pair of X chromosomes, one from each parent. Sex differentiation of the female fetus is governed by the lack of a present functioning SRY gene on either one of the respective sex chromosomes. Female anatomy is distinguished from male anatomy by the female reproductive system, which includes the ovaries, fallopian tubes, uterus, vagina, and vulva. A woman generally has a wider pelvis, broader hips, and larger breasts than a man. These characteristics can facilitate pregnancy, childbirth and breastfeeding. Women typically have less facial and other body hair, have a higher body fat composition, and are on average shorter and less muscular than men. Women are at greater risk of certain diseases like breast cancer, and at lower risk of other diseases like lung cancer.

Obstetrics and gynaecology (also spelled as obstetrics and gynecology; abbreviated as Obst and Gynae, O&G, OB-GYN and OB/GYN) is the medical specialty that encompasses the two subspecialties of obstetrics (covering pregnancy, childbirth, and the postpartum period) and gynaecology (covering the health of the female reproductive system – vagina, uterus, ovaries, and breasts). The specialization is an important part of care for women's health.

Postgraduate training programs for both fields are usually combined, preparing the practising obstetrician-gynecologist to be adept both at the care of female reproductive organs' health and at the management of pregnancy, although many doctors go on to develop subspecialty interests in one field or the other.

The endocrine system is a messenger system in an organism comprising feedback loops of hormones that are released by internal glands directly into the circulatory system and that target and regulate distant organs. In vertebrates, the hypothalamus is the neural control center for all endocrine systems.

In humans, the major endocrine glands are the thyroid, parathyroid, pituitary, pineal, and adrenal glands, and the (male) testis and (female) ovaries. The hypothalamus, pancreas, and thymus also function as endocrine glands, among other functions. (The hypothalamus and pituitary glands are organs of the neuroendocrine system. One of the most important functions of the hypothalamus—it is located in the brain adjacent to the pituitary gland—is to link the endocrine system to the nervous system via the pituitary gland.) Other organs, such as the kidneys, also have roles within the endocrine system by secreting certain hormones. The study of the endocrine system and its disorders is known as endocrinology.The thyroid secretes thyroxine, the pituitary secretes growth hormone, the pineal secretes melatonin, the testis secretes testosterone, and the ovaries secrete estrogen and progesterone.

Roe, (/roʊ/ ROH) or hard roe, is the fully ripe internal egg masses in the ovaries, or the released external egg masses, of fish and certain marine animals such as shrimp, scallop, sea urchins and squid. As a seafood, roe is used both as a cooked ingredient in many dishes, and as a raw ingredient for delicacies such as caviar.

The roe of marine animals, such as the roe of lumpsucker, hake, mullet, salmon, Atlantic bonito, mackerel, squid, and cuttlefish are especially rich sources of omega-3 fatty acids, but omega-3s are present in all fish roe. Also, a significant amount of vitamin B₁₂ is among the nutrients present in fish roes.

Menopause is the time when menstrual periods permanently stop, marking the end of the reproductive stage for the female human. It typically occurs between the ages of 45 and 55, although the exact timing can vary. Menopause is usually a natural change related to a decrease in circulating blood estrogen levels. It can occur earlier in those who smoke tobacco. Other causes include surgery that removes both ovaries, some types of chemotherapy, or anything that leads to a decrease in hormone levels. At the physiological level, menopause happens because of a decrease in the ovaries' production of the hormones estrogen and progesterone. While typically not needed, measuring hormone levels in the blood or urine can confirm a diagnosis. Menopause is the opposite of menarche, the time when periods start.

In the years before menopause, a woman's periods typically become irregular, which means that periods may be longer or shorter in duration, or be lighter or heavier in the amount of flow. During this time, women often experience hot flashes; these typically last from 30 seconds to ten minutes and may be associated with shivering, night sweats, and reddening of the skin. Hot flashes can recur for four to five years. Other symptoms may include vaginal dryness, trouble sleeping, and mood changes. The severity of symptoms varies between women. Menopause is also known to cause thinning and drying of the skin as 30% of the skins collagen is lost during the first five years of menopause. Menopause before the age of 45 years is considered to be "early menopause", and ovarian failure or surgical removal of the ovaries before the age of 40 years is termed "premature ovarian insufficiency".

The menstrual cycle is a series of natural changes in hormone production and the structures of the uterus and ovaries of the female reproductive system that makes pregnancy possible. The ovarian cycle controls the production and release of eggs and the cyclic release of estrogen and progesterone. The uterine cycle governs the preparation and maintenance of the lining of the uterus (womb) to receive an embryo. These cycles are concurrent and coordinated, normally last between 21 and 35 days, with a median length of 28 days. Menarche (the onset of the first period) usually occurs around the age of 12 years; menstrual cycles continue for about 30–45 years.

Naturally occurring hormones drive the cycles; the cyclical rise and fall of the follicle stimulating hormone prompts the production and growth of oocytes (immature egg cells). The hormone estrogen stimulates the uterus lining (endometrium) to thicken to accommodate an embryo should fertilization occur. The blood supply of the thickened lining provides nutrients to a successfully implanted embryo. If implantation does not occur, the lining breaks down and blood is released. Triggered by falling progesterone levels, menstruation (commonly referred to as a "period") is the cyclical shedding of the lining, and is a sign that pregnancy has not occurred.

Ovulation is an important part of the menstrual cycle in female vertebrates where the egg cells are released from the ovaries as part of the ovarian cycle. In female humans ovulation typically occurs near the midpoint in the menstrual cycle and after the follicular phase. Ovulation is stimulated by an increase in luteinizing hormone (LH). The ovarian follicles rupture and release the secondary oocyte ovarian cells.

After ovulation, during the luteal phase, the egg will be available to be fertilized by sperm. If it is not, it will break down in less than a day. Meanwhile, the uterine lining (endometrium) continues to thicken to be able to receive a fertilized egg. If no conception occurs, the uterine lining will eventually break down and be shed from the body via the vagina during menstruation.

An androgen (from Greek andr-, the stem of the word meaning 'man') is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes the embryological development of the primary male sex organs, and the development of male secondary sex characteristics at puberty. Androgens are synthesized in the testes, the ovaries, and the adrenal glands.

Androgens increase in both males and females during puberty. The major androgen in males is testosterone. Dihydrotestosterone (DHT) and androstenedione are of equal importance in male development. DHT in utero causes differentiation of the penis, scrotum and prostate. In adulthood, DHT contributes to balding, prostate growth, and sebaceous gland activity.