FEMALE REPRODUCTIVE SYSTEM

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FEMALE REPRODUCTIVE SYSTEM

The female reproductive system is more complex than that of the male reproductive system. In addition to producing female sex cells, known as ova (eggs), the female body also protects and nurtures a developing baby for about nine months while it grows within the woman’s uterus (womb). A woman’s breasts can provide nourishment for newborns.

BREST

During pregnancy, breast size increases as milk-producing glands known as lobules develop in preparation for breast-feeding. Breast milk can provide all the nourishment a newborn needs. As a newborn breast-feeds, the sucking action stimulates the release of oxytocin, a hormone that promotes milk flow.

OVARIES

The primary reproductive organs of a female are the ovaries, a pair of almond- shaped glands. At puberty, ovaries produce about 400,000 eggs. Each month an egg is released from the ovary and travels down one of the fallopian tubes. If the egg is released around the time of sexual intercourse and it meets and fuses with a male’s sperm, it becomes fertilized. If an egg is not fertilized, it moves from the fallopian tube to the uterus and then passes out of the body in the next menstrual cycle.

 

UTERUS

The uterus is a hollow, muscular organ located on top of the bladder. During pregnancy, a fertilized egg travels to the uterus, embeds within the uterine wall, and forms a fetus . Around 40 weeks after fertilization, the fetus is born. During birth, the baby leaves the uterus and travels through the mother’s vagina, a tube that extends from the uterus to the outside of the body.

Endocrine system

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Endocrine system

The endocrine system is made of many glands—groups of cells that release chemical substances called hormones into the bloodstream. Hormones influence and regulate diverse activities such as metabolism, growth, mental development, and emotional behaviour.

Pituitary gland

The pituitary gland is a pea-sized gland located in the centre of the skull. The pituitary gland acts as a master controlling gland, releasing a number of hormones that activate other glands.

Parathyroid gland

The parathyroid glands are four small glands located in the neck behind the thyroid gland. These glands secrete a hormone that regulates the body’s use of calcium and phosphorus to maintain healthy bones. Parathyroid hormone also affects muscle contraction and the conduction of nerve impulses.

Thyroid gland

The thyroid gland, located in the neck, secretes the hormone thyroxine. Thyroxine increases body metabolism, in which food is broken down and converted into heat and energy. Too little thyroxine in the blood produces lethargy and fatigue, while too much thyroxine results in overactivity, nervousness, and weight loss.

Adrenal gland

The adrenals are two small glands, each located on the top of one kidney. These two glands consist of an inner core, called the adrenal medulla, and an outer area, known as the adrenal cortex. The adrenal medulla releases the hormone epinephrine, which speeds up heart rate and increases blood pressure to help the body cope with emergencies. The adrenal cortex releases hormones that control the level of salts and water in the blood and help regulate the use of sugar. It also secretes small amounts of male sex hormones, or androgens, in both males and females. Of the two parts of the adrenal glands, only the adrenal cortex is under the control of the pituitary gland.

Pancreas

The pancreas is a long, narrow gland located in the abdomen behind the stomach and beneath the liver. The pancreas secretes insulin, a hormone that regulates the body’s use of sugar. When too little insulin is produced, the body tissues cannot use or store sugar, and a disease known as diabetes mellitus develops.

Ovaries

Females have sex glands called ovaries that release hormones called estrogens. These hormones contribute to the development of female sexual characteristics, including skin, hair, and breast development. Estrogens work with certain pituitary hormones to control the menstrual cycle.

Testes

Males have sex glands called testes that secrete androgens, male sex hormones. In addition to contributing to male sexual characteristics, androgens contribute to the production of sperm and the development of the prostate gland.