Google
 

Chapter III - Female Reproductive System

Female Reproductive System

The female reproductive system is very complex and interesting. It is responsible for production of female sex cell called ovum for union with male sex cell called sperm. It is also responsible for nurturing the develop­ing fetus for a period of 9 months until parturition, with the delivery of a fully de­veloped baby. Female reproductive organs may be divided into external organs and in­ternal organs.

Anatomy and Physiology
The external genital organs of the female are collectively known as vulva and comprise Labia majora, labia minora, clitoris, and Bartholin glands.

Internal reproductive organs include ova­ries, fallopian tubes, uterus, and vagina.

The human female reproductive system contains two main parts: the vagina and uterus, which act as the receptacle for the male's sperm, and the ovaries, which produce the female's ova. All of these parts are always internal; the vagina meets the outside at the vulva, which also includes the labia, clitoris and urethra. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the fallopian tube into the uterus.

If, in this transit, it meets with sperm, the sperm penetrate and merge with the egg, fertilizing it. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then implants itself in the wall of the uterus, where it begins the processes of embryogenesis and morphogenesis. When developed enough to survive outside the womb, the cervix dilates and contractions of the uterus propel the fetus through the birth canal, which is the vagina.

The ova are larger than sperm and are generally all created by birth. Approximately every month, a process of oogenesis matures one ovum to be sent down the Fallopian tube attached to its ovary in anticipation of fertilization. If not fertilized, this egg is flushed out of the system through menstruation.

So lets study about each part in detail.

Vagina

The vagina is the tubular tract leading from the uterus to the exterior of the body in female mammals, or to the cloaca in female birds and some reptiles. Female insects and other invertebrates also have a vagina, which is the terminal part of the oviduct.

The vagina is the place where semen from the man is deposited into the woman's body during sexual intercourse.

The human vagina is an elastic muscular tube about 4 inches (100 mm) long and 1 inch (25 mm) in diameter that connects the vulva at the outside to the cervix of the uterus at the inside. If the woman stands upright, the vaginal tube points in an upward-backward direction and forms an angle of slightly more than 45 degrees with the uterus. The vaginal opening is at the back (caudal) end of the vulva, behind the opening of the urethra. Above the vagina is Mons Veneris. The inside of the vagina is usually pink, as with all internal mucous membranes in mammals.

Length, width and shape of the vagina may vary. When a woman gives birth and during sexual intercourse, the vagina widens and lengthens up to 2-3 times.

Vaginal lubrication is provided by glands near the vaginal opening and the cervix and also seeps through the vaginal wall (which does not contain any glands).

The hymen—a membrane situated behind the urethral opening—partially covers the vagina in many organisms, including some human females, from birth until it is ruptured by sexual intercourse, or by any number of other activities including medical examinations, injury, certain types of exercise, introduction of a foreign object, etc.

Functions of the vagina
From a biological perspective, the vagina performs the following functions:

· Providing a path for menstrual fluids to leave the body.
· Giving birth
· Admitting the male penis for sexual intercourse

Sexual intercourse
The vagina admits the male penis for sexual intercourse and ultimately male sperm for the fertilization of ova for reproduction. The concentration of nerve endings particularly close to the mouth of the vagina causes pleasure to be experienced during sexual activity. The opening of the vagina is home to the clitoris, which is located at the anterior of the vaginal opening; for most women, the clitoris is the main source of sexual pleasure (although it can be too sensitive for direct stimulation in some women). Some women have a very sensitive erogenous zone called "the G-spot" inside their vagina (in the anterior of the vagina, about five cm. in from the entrance), which can produce very intense orgasms if stimulated properly, possibly responsible for the disputed female ejaculation. Not all women have a g-spot that is responsive to stimulation, however.

Sexual health and hygiene
Other than the penis, fingers or sexual devices, many women insert tampons during menstruation. These must be regularly changed - every four hours at most. Other objects inserted include diaphragms (placed against the cervix, blocking it from sperm), spermicidal cream and lubricant. Additionally, some women use vaginal douches, which serve to cleanse the vagina with a gentle soap intended to remove odor. These days such treatment is advised against by doctors, as it may upset the balance of bacteria in the vagina, rather than helping it. Thus, the vagina itself needs no particular treatment in the name of basic hygiene.

The vagina is examined during gynecological exams, often using an instrument called a speculum, which keeps the vagina open for visual inspection or taking of samples (see pap smear).

Various disorders can affect the vagina, including vaginal cancer and yeast infections.

No comments: