Reproductive organs are the internal and external sex organs (genitals) and the gonads, i.e., the testicles in men and the ovaries in women.

The gonads mature during puberty under the control of hormones from the pituitary gland. The same flow of hormones causes the formation of the sex hormones in the gonads: testosterone and androgens in men progesterone, and estrogens in women.

reproduction

Sexual organs enable the emergence of new human life. An egg cell matures in the female ovaries every month. The male testicles produce sperm cells, which during sexual intercourse, travel through the man’s spermatic ducts and penis into the woman’s vagina. Here, they meet the egg in the womb (uterus). One of the sperm enters the egg and fertilizes it.

Only a few sperm cells penetrate the fallopian tube (tuba uterine), where the mature egg remains viable for four to five hours after ovulation. So, union with a sperm cell (conception) is only possible in the first few hours after ovulation.

In fertilization, a sperm cell enters the egg cell, and their respective nuclei fuse into a shared core. The fertilized egg cell now has the complete set of 46 chromosomes and begins cell division. It travels from the fallopian tube to the uterus, where it implants itself on the posterior wall of the uterine body around the sixth day after conception. The placenta that subsequently forms allows the embryo – as the unborn child is called in the first eight weeks after fertilization – to contact the maternal blood vessels. In this way, an exchange of substances can occur in that the blood enriched with oxygen and nutrients is supplied via the umbilical vein.

In contrast, two umbilical arteries transport the fetal blood via the umbilical cord to the placenta. This ensures that the fetus is fed (designated from the eighth week of pregnancy) during pregnancy. At ten weeks, the fetus is about 18 centimeters long; by nine months, the baby usually weighs more than three kilograms.

In the confusingly similar twins, a single egg fertilized by a sperm cell is divided into two embryos, while the dissimilar twins come from two eggs fertilized by two spermatozoa.

Contraception refers to various methods that prevent a woman from becoming pregnant. The safest and most common form of contraception is the prescription birth control pill. Hormones in it ensure that the egg cells in the ovaries do not mature.

A mechanical device that, when used properly, protects against AIDS and various sexually transmitted diseases at the same time is the condom: a rubber sheath that is placed over the penis and prevents the sperm and egg cells from meeting. Other means that are over the counter, like the condom – for example, foam suppositories – do not offer such reliable protection.

In addition, there are other contraceptive methods for women, which must be discussed with the gynecologist after a gynecological examination. The “pill for men” is still in the development stage.

uterus

The uterus, approximately eight centimeters long, lies in the small pelvis. It consists of the cervix, the cervix, and the body of the uterus. During a woman’s fertile period (from puberty to menopause), the uterine lining develops monthly to be an optimal breeding ground for a fertilized egg. If fertilization does not occur, a large part of this special mucous membrane is shed during menstrual. In the next cycle, the mucous membrane rebuilds itself again.

In the case of fertilization leading to pregnancy, the uterus enlarges and stops contracting its muscle fibers throughout the pregnancy. Only when the fetus is fully grown do the contractions begin again: labor begins. The cervix (Portio vaginalis cervicis) and vagina (vagina) expand and thereby enable birth. After birth, the uterus quickly recedes under the influence of hormones.

During pregnancy, the placenta is built up from the uterine lining and is shed again after birth. But before that, it gives the unborn child everything it needs to live: a supply of oxygen and nutrients from the mother’s blood while at the same time disposing of waste materials – such as carbon dioxide – from its small circulatory system. The placenta temporarily fulfills the function of all of the human’s vital organs. At the end of the pregnancy, she weighs about half a kilogram.

testicles

The testicles are located in the scrotum outside the body; Inside it, it would be too warm for them: the formation of sperm cells requires a temperature that is three to five degrees Celsius lower than body temperature. Tight clothing, for example, can also reduce a man’s fertility.

In addition to the sperm, the testicles produce special cells that form the “male” and produce the hormone testosterone. This hormone is responsible for the development of secondary male sexual characteristics, such as a deep voice and beard growth.

Behind the testicles lies the epididymis. The sperm the testicle produces is collected and stored in its tube system. The epididymis tubes open into the vas deferens, which in turn flows into the urethra.

Male sexual organs

The male sexual organs are the penis, the scrotum, the prostate, the seminal vesicles and the vas deferens.

Penis

The penis hangs outside the body in front of the scrotum. It measures six to twelve centimeters in length. The three-column-like corpora cavernosa that it contains enlarges it to ten to twenty centimeters during sexual arousal. By filling with arterial blood, they erect the penis so that it can penetrate the woman’s vagina.

The shaft of the penis begins at the pelvic floor with the root of the penis and ends at the tip with the glans penis, which is separated from the shaft of the penis by an annular groove. The urethra (urethra), through which semen escapes in addition to urine during orgasm, ends in the tip of the penis (Orificium urethrae externum).

puberty

Puberty is the period of human life in which children become women and men. The physical characteristics change; The sexual organs and their functions mature, and sexual interest influences mental feelings. This process occurs earlier in girls than in boys. A brain gland that stimulates the production of sex hormones is responsible for puberty: the pituitary gland. It causes the hormone estrogen to be produced in the ovaries of girls and testosterone in the testicles of boys. Mental changes also take place at the same time as the physical development process.

The young person must, on the one hand, come to terms with their own body and, on the other hand, with a new position in life and assert themselves. The confrontation with the environment is therefore becoming more intense, and with it the problems that can arise, for example in relationships with parents or other people. The process is completed between the ages of 18 and 22 (earlier for women than for men). During this time the body is at its greatest performance.

Sperm cells

Up to thirty billion sperm cells are formed in the seminiferous tubules of the testicles every month. They are stored in the coiled tube system of the epididymis and develop there to full maturity in 60 to 72 hours. If no ejaculation occurs, the cells dissolve again.

A sperm cell resembles a tiny tadpole. It consists of a head, neck, middle section and tail, which enables the cell to move. Each testicle produces approximately 50 million sperm cells per day. They are either expelled during ejaculation or broken down after a few days and replaced by new ones.

Female breast

The female breast is a glandular structure with stored fat and fibrous tissue. About twenty lobules with milk glands surround the nipple in a circle. When it is cold or sexually aroused, it contracts and stands upright.

During pregnancy, the mammary glands in the mother’s breast expand under the influence of hormones and produce milk (lactation) shortly after birth. This milk contains the optimal mix of nutrients that the baby needs for its growth in the first months of life. After its birth, it now needs around 600 grams of milk per day, and after about eight months, it can also eat solid food.

Many substances contained in breast milk can be replaced with ready-made milk, but not all of them. Breastfeeding also provides the baby with important antibodies from the mother, which protect against many diseases. Breast milk contains half as much protein, twice as much sugar and the same amount of fat as cow’s milk.

Female genital organs

The female reproductive organs form eggs and nourish them in the event of fertilization.

The labia and clitoris are the female’s external genitalia. The two labia majora form a thick fold of skin that merges backwards into the perineum and forwards into the well-padded skin above the pubic bone: the mons pubis. The small ones lie between the large labia. In the front part they form a unit and protect the sensitive clitoris. In the rear part they flow into the Scheidendamm.

 

In a young girl, the entrance to the vagina is almost completely closed by the hymen. The hymen is a very thin, perforated fold of mucous membrane at the opening of the vagina. It is penetrated during the first sexual act, this process is called defloration.

Just as physical and mental changes occur during puberty, this happens again in women during the so-called climacteric, also known as menopause. They usually start between the ages of 45 and 55. The changed mental state during this time, often reflected in tension and stress, is closely related to physical changes.

The decrease in sex hormones and the cessation of menstrual bleeding are often accompanied by symptoms such as hot flashes, irritability, fatigue and depression. This condition lasts for a few months or even years. Medical hormone replacement treatments can improve general well-being, but – like the birth control pill – are controversial due to an assumed

The female breast is a glandular structure with stored fat and fibrous tissue. About twenty lobules with milk glands surround the nipple in a circle. When it is cold or sexually aroused, it contracts and stands upright.

During pregnancy, the mammary glands in the mother’s breast expand under the influence of hormones and produce milk (lactation) shortly after birth. This milk contains the optimal mix of nutrients that the baby needs for its growth in the first months of life. After its birth it now needs around 600 grams of milk per day; and after about eight months it can also eat solid food.

Many substances contained in breast milk can be replaced with ready-made milk, but not all of them: Breastfeeding also provides the baby with important antibodies from the mother, which protect against many diseases. Breast milk contains half as much protein, twice as much sugar and the same amount of fat as cow’s milk.

Female genital organs

The female reproductive organs form eggs and nourish them in the event of fertilization.

The labia and clitoris are the female’s external genitalia. The two labia majora form a thick fold of skin that merges backwards into the perineum and forwards into the well-padded skin above the pubic bone: the mons pubis. The small ones lie between the large labia. In the front part they form a unit and protect the sensitive clitoris. In the rear part they flow into the Scheidendamm.

 

In a young girl, the entrance to the vagina is almost completely closed by the hymen. The hymen is a very thin, perforated fold of mucous membrane at the opening of the vagina. It is penetrated during the first sexual act, this process is called defloration.

Just as physical and mental changes occur during puberty, this happens again in women during the so-called climacteric, also known as menopause. They usually start between the ages of 45 and 55. The changed mental state during this time, often reflected in tension and stress, is closely related to physical changes.

The decrease in sex hormones and the cessation of menstrual bleeding are often accompanied by symptoms such as hot flashes, irritability, fatigue and depression. This condition lasts for a few months or even years. Medical hormone replacement treatments can improve general well-being, but – like the birth control pill – are controversial due to an assumed risk of cancer.