The Male Reproductive Anatomy consists of the
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Testes and scrotum
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Penis
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Seminal Vesicles, prostate glands, bulbourethral glands
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Epipidymis, vas deferens, urethra
Testes form the primary reproductive organs or gonads for the male, and are responsible for the production of sperm. The testes are suspended outside the body cavity by scrotum.
The penis deposits sperm in the female. It is surrounded by erectile tissue (vascular). Erection is a parasympathetic spinal reflex to tactile and other stimulation enhanced by sympathetic inhibition, resulting from the gorging of erectile tissue with blood.
The seminal vesicles, prostate gland, and bulbourethral glands provide the bulk of the semen, a mixture of secretions, sperm and mucous. The seminal vesicles produce fructose and prostaglandins; while alkalinity and clotting enzymes are secreted by the prostate gland. The bulbourethral glands, on the other hand, secretes the lubricants during intercourse.
The epididymis, vas deferens and urethra form the ejaculation route for the exit of sperm. Sperm are initially stored in the ductus deferens. During emission phase of ejaculation, sperm are emptied into the urethra by sympathetically induced contractions. These motor neuron induced contractions of skeletal muscles at the base of penis expel the semen during the expulsion phase of ejaculation. Ejaculation is a part of orgasm.
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Male Growth and Development
As a male reaches puberty, the testes (testicles) start producing both sperm and testosterone; the male hormone that helps maintain the male sexual characteristics. As sperm are produced, they pass from the testes through the coiled channels of the epididymis, an organ that stores and nourishes them as they mature.
Once sperm are completely mature, they move into the vas deferens. This tubal structure connects the epididymis with the seminal vesicles, the two pouchlike glands that provide storage for the mature sperm. The entire process of sperm formation to maturation takes about 72 days.
When a man ejaculates (or expels the fluid from his penis) during intercourse, sperm from the seminal vesicles combine with a thick fluid from the prostate gland to create semen. This fluid (or ejaculate) is deposited into the woman's vagina.
Once ejaculated, the semen liquefies, and motile sperms will swim towards the fallopian tube to fertilise a waiting ovum, if any. The probability of successful conception is dependent on various factors such as the quality of the sperm as well as the "environmental conditions" in the vagina.
The Female Reproductive Anatomy consists of
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Vagina
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Uterus
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Ovaries
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Fallopian tubes
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Cervix
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Endometrium
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Bartholin gland
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Vulva, labia majora, labia minora and clitoris
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Hymen
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Bladder
Female Growth and Development
The vagina connects the vulva to the uterus, serving both as a receptacle for sperm during sexual intercourse and as the passageway for the infant during birth.
The uterus is the muscular organ where a fertilized egg attaches and develops. It is about the size and shape of a pear, and is lined with a rich and nourishing mucous membrane called the endometrium.
From the top of the uterus extend the fallopian tubes, which lead backward and downward to the ovaries. These are the two small sacs that contain the eggs. A woman is born with about 400,000 eggs. Each month during her reproductive years, usually only a single egg, or ovum, matures. The egg matures inside a follicle within an ovary. At mid-cycle, the egg is released from the follicle in a process called ovulation. The egg then enters and travels down one of the fallopian tubes toward the uterus. When the egg reaches the end of the fallopian tube, it is ready for fertilization by the man's sperm.
The breasts are the milk "factory" for breastfeeding the baby. Within the breasts are tiny glands that produce milk to nourish a new-born baby.
From the onset of puberty, until a woman reaches menopause, she will experience monthly bleeding cycles, called menstruation or period. Menstrual blood results from the shedding of the uterine lining from the previous cycle whenever a released ovum is not fertilised and conception does not occur. It is generally thin with dark red jelly-like clots and flows between 2 to 6 days per menstrual cycle.
Overview of a "Normal" Menstrual Cycle
Menstruation
Day 1 of your cycle is the first full day of menstrual bleeding. The uterine lining built up in the previous cycle is cleared away, and the hormone levels from the previous cycle take a sharp decline, causing the physical and emotional symptoms commonly associated with menstruation.
Pre-Ovulation
The pituitary gland releases a hormone called FSH (Follicle Stimulating Hormone), which stimulates an ovarian follicle to grow and an egg to mature. The pituitary gland also releases LH (Luteinizing Hormone) which stimulates the follicle to manufacture and secrete estrogen. Estrogen causes the uterine lining to grow.
Ovulation
The pituitary gland releases a heavy surge of LH. 24 to 36 hours after the surge, the follicle will rupture, releasing the matured egg to the fallopian tube. The remainder of the ruptured follicle (called the corpus luteum) recedes back to the ovary and begins to secrete progesterone. Progesterone causes an increase in blood vessels to the uterine lining, inhibits other eggs from developing, and causes the Basal Body Temperature (BBT) to rise about half a degree.
Luteal Phase
The luteal phase is the period of time (usually 11-14 days) following ovulation. The egg can be fertilized within 24 hours of release, while it is still in the fallopian tubes. If the egg is fertilized, the pituitary gland produces hCG which causes the increased production of progesterone. The progesterone in turn causes the BBT to remain high throughout the luteal phase and after the 14th day. High progesterone levels are also responsible for "morning sickness" and other symptoms of pregnancy. If the egg is not fertilized within 24 hours, the corpus luteum regresses and slows its progesterone production. After around 11-14 days, there is no longer enough progesterone to supply the uterine lining with blood, and so menstruation begins anew.
Menopause
Menopause is defined as the end of menstruation. Medically this is confirmed by not having a period for 12 months, in a row, due to a depletion of ovarian follicles (eggs). Menstruation may occur from the ages of 45 to 55 years - on average at about age 51 - but it can occur as early as in a woman's 30s and as late as in her 60s. Menopause is not a disease, but a natural event - the end of fertility - resulting from the ovaries slowing down production of two sex hormones: estrogen and progesterone.
Changes in the hormone levels, however, may give rise to symptoms that affect a woman psychologically and physiologically. Amongst others, these may include:
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Mood changes, forgetfulness, difficulty concentrating,
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Depression,
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Hot flushes, excessive sweating,
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Dryness of the vagina, discomfort with intercourse,
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Lowered sex drive,
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Incontinence (involuntary leaking of urine),
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Osteoporosis (thinning of bones), etc.