Reproduction

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The male sex organs

The penis is easier to see than the vulvar. It hangs away from the body. Often a foreskin covers the glans of the tip of the penis. If it is not present, it usually means that the foreskin was removed when the boy was still a baby in an operation called a circumcision. The two testicles, hang beneath the penis in a sac called the scrotum. The scrotum protects the testes and makes sure that the temperature is right for the making of sperm.

Internal male genitals

The internal male genitals are: the testes, the epididymides, the vasa deferentia, the seminal vesicles, the prostate gland, and the Cowper’s glands.

The two testes sit in the scrotum. They are oval-shaped and it is here that the sperm and male sex hormones are made. They are very sensitive to touch and pressure. The hormone called testosterone, is responsible for the development of the male sexual characteristics such as pubic and armpit hair, and muscles.

The epididymides are the two, coiled tubes in the testes. This is where the sperm develops and is stored until they are released during ejaculation.

The vasa deferentia are the paired tubes that carry the mature sperm from the epididymides to the urethra.

The seminal vesicles are a pair of special sacs that makes about 60% of the fluid that makes up the semen in which sperm are transported. This fluid provides nourishment for sperm.

The prostate gland is a walnut-sized, glandular structure that makes about 30% of the fluid that makes up semen.

The male genitals are present in the body at birth, but they're not sexually active until adolescence. At puberty the testes, penis and scrotum begin to grow. The genitals are mature when the testes produce functional sperm. Every day a man makes between 50 and 500 million sperm.

Puberty is the time during teenage years when males start to produce sperm, and females start to release eggs. Puberty occurs a couple of years earlier for females than males usually.
Menopause is the time when females stop releasing eggs.
This usually occurs between 45 to 55 years of age. However, males produce sperm all their lives following puberty.

The organs of sexual reproduction are the gonads , which are the ovaries in females and the testes in males. Females produce female gametes, (eggs); males produce male gametes, (sperm).

Fertilisation

When a female is born, each of her ovaries has hundreds of thousands of eggs, but they remain dormant until her first menstrual cycle, which occurs during puberty. At this time, during adolescence, the pituitary gland secretes hormones that stimulate the ovaries to produce female sex hormones, including oestrogen, which helps the female develop into a sexually mature woman. Every 28 days or so from puberty until menopause, a complex set of hormonal events trigger between one and three eggs, the size of the head of a pin, to be released from the follicles in the ovaries. The release of luteinizing hormone (LH) from the pituitary gland in your brain triggers the mature follicle to rupture and the egg, or eggs, are propelled towards the fallopian tubes towards the Uterus. This whole process takes about three minutes and is known as ovulation. Sexual reproduction is the fertilization of a female gamete by a male gamete.

Before ovulation, the cervix produces a special mucous for about 3 to 9 days. This mucous is as crucial to fertility as ovulation because without it, the male’s sperm cannot survive nor be transported inside the female to fertilize the eggs. When mucous is present, it nourishes and protects sperm allowing them to live for 3 to 5 days.

Reproduction

Human reproduction is much the same for all mammals. It is the hallmark of life – essential for the cycle of living things. Conception refers to fertilisation of the female egg by the male sperm. When an egg is released from one of the ovaries at ovulation, between day 9 and day 16 of the menstrual cycle, it makes its way down the fallopian tube to the already prepared uterus. During intercourse, the male ejaculates; about one tenth of an ounce of semen is deposited into the vagina. Between 200 and 300 million sperm are in this small amount of semen. If a female and male have sexual intercourse within several days of ovulation, fertilization can occur. The sperm travels through the cervix into the upper part of the uterus and then into the fallopian tubes where the sperm meets the egg. If the sperm manages to enter the egg, it becomes fertilised and a new life can begin. It takes only one sperm to fertilize the egg.

Just as everything in our universe is cyclic, the change from day to night, the pattern of the seasons, the cycle of life and death – so every aspect of a woman’s reproductive system is cyclic from the menstrual cycle itself to the fertile phase and on to post-menopausal non-fertility phase of a woman’s life. Things that can interfere in this natural cycle are birth control pills, Hormone Replacement Therapy (HRT), and other forms of hormonal intervention as well as poor diet, poor hygiene and stress.