Healthy man and woman. The human reproductive system. reproductive health. The reproductive system is the reproductive system responsible for the function of reproduction. Reproductive health is the health of the reproductive system. Manifestation of metabolic endocrine disorders

All living beings reproduce. Reproduction - the process by which organisms create more organisms like them - is one of the things that distinguishes living things from non-living things.

In humans, the male and female reproductive systems work together to make a baby. In the human reproductive process, two types of germ cells or gametes are involved.

A male gamete, or sperm, and a female gamete, an egg or ovum, meet in a woman's reproductive system to create a child. The male and female reproductive systems are essential for reproduction.

People pass on some characteristics of themselves to the next generation through their genes, special carriers of human traits.

Parents of genes pass on to their offspring what makes children like others in theirs, but they also make each child unique. These genes come from the father's sperm and mother's eggs, which are produced by the male and female reproductive systems.

Understanding the male reproductive system, what it does, and the issues that can affect it can help you better understand your child's reproductive health.

About the male reproductive system

Most species have two sexes: male and female. Each gender has its own unique reproductive system. They differ in shape and structure, but both are specifically designed to produce, feed, and transport either eggs or sperm.

Unlike the female, whose reproductive organs are located entirely inside the pelvis, the male has reproductive organs, or sex organs, that are both inside and outside the pelvis. The male genitalia include:

• testicles;
• the duct system, which consists of the epididymis and the vas deferens;
• accessory glands, which include the seminal vesicles and the prostate gland;
• penis.

In a pubescent guy, the two testicles (or testicles) produce and store millions of tiny sperm cells. The testicles are oval and about 2 inches (5 centimeters) long and 1 inch (3 centimeters) in diameter.

The testicles are also part of the endocrine system as they produce hormones including testosterone. Testosterone is a major part of puberty in boys, and as a guy makes his way through puberty, his testicles produce more and more.

Testosterone is the hormone that causes boys to produce deeper voices, bigger muscles, body and facial hair, and stimulates sperm production.

Along with the testicles are the epididymis and the vas deferens, which make up the ductal system of the male reproductive organs.

Seed oozing is a muscular tube that runs up along the testicles and transports a spermatic fluid called semen. The epididymis is a set of coiled tubes (one for each testicle) that connects to the seed of the seed.

The epididymis and testicles hang in a pouch-like shape behind the pelvis, called the scrotum. This bag of skin helps regulate the temperature of the testicles, which must be cooler than body temperature in order to obtain sperm.

The scrotum changes size to maintain the correct temperature. When the body is cold, the scrotum contracts and becomes stiffer to retain body heat.

As it heats up, the scrotum becomes larger and more flexible to get rid of the extra heat. It happens without the guy thinking it through. The brain and nervous system give the scrotum a cue to resize.

Accessory glands, including the seminal vesicles and the prostate gland, provide fluids that lubricate the duct system and nourish the sperm. The seminal vesicles are sac-like structures attached to the vas deferens towards the bladder.

The prostate gland, which produces some of the semen, surrounds the ejaculatory ducts at the base of the urethra, just below the bladder.

The urethra is the duct that carries semen out of the body through the penis. The urethra is also part of the urinary system because it is also the channel through which urine passes as it leaves the bladder and exits the body.

The penis actually consists of two parts: the shaft and the glans. The shaft is the main part of the penis, and the glans is the tip (sometimes called the glans).

At the end of the head is a small slit or opening through which seeds and urine exit the body through the urethra. The inside of the penis is made up of spongy tissue that can expand and contract.

All boys are born with a foreskin, a fold of skin at the end of the penis that covers the glans. Some boys are circumcised, which means that a doctor or clergyman cuts off the foreskin.

Circumcision is usually done during the first few days of a boy's life. While circumcision is not a medical necessity, parents who choose to circumcise their sons often do so based on religious beliefs, hygiene concerns, or cultural or social reasons.

Boys who have circumcised penises and those who don't are no different: all penises work and feel the same, whether or not the foreskin has been removed.

What does the male reproductive system do

The male reproductive organs work together to produce and release sperm into the female's reproductive system during intercourse. The male reproductive system also produces sex hormones that help a boy develop into a sexually mature person during puberty.

When a boy is born, he has all parts of his reproductive system in place, but until puberty cannot reproduce. When puberty begins, usually between the ages of 9 and 15, the pituitary gland — which is located near the brain — releases hormones that stimulate the testicles to produce testosterone.

The production of testosterone leads to many physical changes. Although the timing of these changes is different for each guy, the stages of puberty usually follow a predetermined sequence:

• During the first stage of male puberty, the scrotum and testicles grow.
• Then the penis becomes longer, and the seminal vesicles and prostate gland grow.
• Hair begins to grow in the pubic area and then on the face and armpits. At this time, the boy's voice also intensifies.
• Boys also have a growth spurt during puberty as they reach their adult height and weight.

Sperm

Men who have reached puberty produce millions of sperm cells every day. Each sperm is extremely small: only 1/600 of an inch (0.05 millimeter). Sperm develops in the testicles in a system of tiny tubes called seminiferous tubules.

At birth, these tubules contain simple, round cells, but during puberty, testosterone and other hormones cause these cells to transform into sperm.

Cells divide and change until they have a head and a short tail like tadpoles. The head contains the genetic material (genes).

The sperm use their tails to push themselves towards the epididymis where they complete their development. It takes about 4-6 weeks for sperm to pass through the epididymis.

The sperm then passes to the vas deferens or the spermatozoon. The seminal vesicles and prostate produce a whitish fluid called seminal fluid, which mixes with semen to form semen when a male is sexually stimulated.

The penis, which usually hangs, becomes heavy when a man is sexually aroused. The tissues in the penis fill with blood and become hard and erect (erection). The stiffness of the penis makes it easier to insert into a woman's vagina during intercourse.

When the penis is stimulated, the muscles around the reproductive organs contract and force semen to pass through the duct system and urethra. The semen is pushed out of the man's body through the urethra, a process called ejaculation. Every time a guy ejaculates, he can contain up to 500 million sperm.

When a female ejaculates during intercourse, sperm is deposited in the female's vagina. From the vagina, semen makes its way through the cervix and travels through the uterus with the help of uterine contractions.

If a mature egg is in one of the female fallopian tubes, a single sperm can enter, as well as fertilization or conception. This fertilized egg is now called a zygote and contains 46 chromosomes - half of the egg and half of the sperm.

The genetic material from a man and a woman is combined in such a way that a new person can be created. The zygote divides again and again as it grows in the female womb, maturing over the course of pregnancy into an embryo, fetus, and finally a newborn baby.

Boys can sometimes have problems with their reproductive system, including:

Traumatic trauma

Even mild trauma to the testicles can cause severe pain, bruising, or swelling. Most testicular injuries occur when the testicles are struck or crushed, usually during sports or other injury.

Testicular torsion when one of the testicles twists around, cutting off its blood supply, is also a medical emergency that is thankfully not common. Surgery is needed to unwind the cord and save the testicle.

Varicocele

This is a varicose vein (abnormally swollen vein) in the network of veins that run from the testicles. Varicoceles often develop while a boy is going through puberty.

A varicocele is not usually harmful, but it can damage the testicle or reduce sperm production. Take your son to see your doctor if he is concerned about changes in his testicles.

testicular cancer

It is one of the most common types of cancer in men under 40 years of age. This happens when cells in the testicle divide abnormally and form a tumor.

Testicular cancer can spread to other parts of the body, but if it is found early, the rate of cure is excellent. Adolescent boys should be encouraged to learn how to perform testicular self-examinations.

Epididymitis

This is an inflammation of the epididymis, the coiled tubes that connect testes to testes. It is usually caused by an infection such as sexually transmitted chlamydia and results in pain and swelling near one of the testicles.

Dropsy

A hydrocele is when fluid collects in the membranes surrounding the testicles. Hydrocells can cause swelling in the scrotum around the testicle, but are usually painless. In some cases, surgery may be required to correct the condition.

Inguinal hernia

When part of the intestine penetrates through an abnormal opening or weakening of the abdominal wall and into the groin or scrotum, it is known as an inguinal hernia. A hernia may look like a bulge or swelling in the groin area. She is treated with surgery.

Disorders affecting the penis include:

• Inflammation of the penis. Symptoms of penile inflammation include redness, itching, swelling, and pain. Balanitis is when the glans (head of the penis) become inflamed. Posthit is an inflammation of the foreskin, usually due to a yeast or bacterial infection.
• Hypospadias. In this disorder, the urethra opens at the underside of the penis rather than at the tip.
• Phimosis. This is tightness of the foreskin and is common in newborns and young boys. It usually gets better without treatment. If this interferes with urination, circumcision (removal of the foreskin) may be recommended.
• Paraphimosis. This can develop when the foreskin of a boy's uncircumcised penis is retracted (ripped off to expose the glans) and trapped so that it cannot be returned to an unprofitable position. As a result, blood flow to the head of the penis may be affected and the boy may have pain and swelling. The doctor may use a lubricant to make a small incision so that the foreskin can be pulled forward. If that doesn't work, circumcision is recommended.
• Ambiguous genitals. In most boys born with this disorder, the penis may be very small or non-existent, but testicular tissue is present. In a small number of cases, a child may have both testicles and ovarian tissue.
• Micropenis. This is a disorder in which the penis, although normally formed, is significantly below average size as defined by standard measurements.

If your son has symptoms, problems with his reproductive system, talk to your doctor - many problems with the male reproductive system can be treated. The doctor is also a good resource for your son if he has questions about growth and sexual development.

Studepedia.org is a constantly updated large database of educational materials (at the moment 166 thousand 848 articles) for students and teachers.

SYSTEM OF SPECIAL EXERCISES FOR WORKING FULL READING AND WRITING SKILLS (Pedagogy)

We teach to read and write without errors: A set of exercises (Pedagogy)

HISTORY OF PSYCHOLOGY from antiquity to the middle of the 20th century. 1 page (Psychology)

SOCIOLOGY (Sociology)

Methods for the development of coherent speech in children with systemic underdevelopment of speech (Pedagogy)

Life of Galileo 1 page (Philosophy)

Miracle fasting 1 page (Medicine, Health)

Erich Fromm. Man and woman (Psychology)

Buying a car (Finance, Management)

Appointments of gears and gears. (Engineering)

GOLDEN LOTUS, COLLECTION OF FANTASTIC NOVELS AND STORIES (Literature)

Painting of the XX Century (Culture, Art)

Project development of an automated animal feeding line using insect larvae as live food (Agronomy, Agriculture)

On the culture of scientific research – 1 page (Psychology)

Jacque Fresco, Roxanne Meadows - The Best Money Can't Buy (Philosophy)

Article 5. Independence of Trade Unions (Law)

Ernst Unknown. Formation of style. 1950-1960 (Culture, Art)

Request for Information (Right)

Accounting for the anatomical and physiological characteristics of children in the organization of their motor activity (Sports)

Prologue in Heaven (Literature)

Topic 1. Introduction. The role of science and technology in the history of mankind (Natural Science)

Family is a world in which we are comfortable (Pedagogy)

EPIGRAPH 1 page (Learning languages)

The main characteristics of the electric current. (Electronics)

Design a local area network (LAN) for a company (Informatics)

Working with records and one-dimensional arrays. (Computer science)

Simple geometric calculations. (Mathematics)

Simple calculations with numbers of integer and real types. (Computer science)

The structure of the enterprise and the organizational structure of management (Finance, Management)

Plant Organs (Biology, Zoology, Anatomy)

First | Previous | 1 | 2 | 3 | Next | Last

REPRODUCTIVE ORGANS

REPRODUCTIVE ORGANS(from the Latin re- - a prefix, here meaning renewal, repetition and produco - I create), organs of plants and animals that perform the functions of reproduction. In plants, the reproductive organs are various structures that provide vegetative, asexual, and sexual reproduction.

The reproductive organs of prokaryotes, in which the sexual process and alternation of generations are absent, are represented by resting spores, hormogonies, etc.

Studepedia.org - these are Lectures, Manuals, and many other materials useful for studying

The reproductive organs of many fungi, algae, as well as moss and ferns, horsetails and lycopsids with a pronounced alternation of generations (sporophyte and gametophyte) are represented by sporangia (asexual) and gametangia (sexual reproduction). In higher seed plants (gymnosperms and angiosperms), the alternation of generations of which acts in a latent form and the daughter sporophyte (seed embryo) develops on the maternal sporophyte, the reproductive organs, in the strict sense, are micro- and megasporocytes, generative cells of dust particles and eggs.

However, the term reproductive organs is often used in a broader sense, including such complex generative structures as angiosperm flowers and fruits, gymnosperm strobili (male and female cones), etc. Reproductive organs also include organs of vegetative propagation.

The reproductive organs in animals are more commonly referred to as the sex organs.

The structure of the human reproductive system

In order for parenthood to be responsible, so that desired and healthy children are born, every modern person must know how to maintain their reproductive health:

<Репродуктивное здоровье – это состояние полного физического, умственного и социального благополучия при отсутствии заболеваний репродуктивной системы на всех этапах жизни.

<Репродуктивная система – это совокупность органов и систем организма, обеспечивающих функцию воспроизводства (деторождения).

The foundations of reproductive health are laid in childhood and adolescence. There is an opinion: everything connected with the birth of a future life depends entirely on the health of the future mother.

Reproductive system of a woman

The main process of the menstrual cycle is the maturation of an egg capable of fertilization. In parallel, the mucous layer of the uterus (endometrium) is being prepared for the adoption of a fertilized egg (implantation).

In order for both processes to occur in the desired sequence, hormones exist.

Rice. 29. Organs of the female reproductive system

The process of egg formation - oogenesis (ovogenesis) and the synthesis of female sex hormones occurs in the female sex glands - the ovaries. The ovaries vary in size, shape, and mass depending on age and individuality. In a woman who has reached puberty, the ovary looks like a thickened ellipsoid weighing from 5 to 8 g.

The right ovary is somewhat larger than the left. In a newborn girl, the mass of the ovary is approximately 0.2 g. At the age of 5, the mass of each ovary is 1 g, 8-10 years old - 1.5 g, 16 years old - 2 g.

The ovary consists of 2 layers: cortical and cerebral. In the cortical layer, eggs are formed (Fig. 30).

Rice. 30. Human egg

The medulla is made up of connective tissue containing blood vessels and nerves.

Female egg cells are formed from primary egg germ cells - oogonia, which, together with nourishing cells - follicular - form primary egg follicles. Each egg follicle is a small egg cell surrounded by a row of flat follicular cells. In newborn girls, they are numerous and almost adjacent to each other, and in old age they disappear.

In a 22-year-old healthy girl, 400,000 primary follicles can be found in both ovaries. During life, only 500 primary follicles mature and produce eggs capable of fertilization, while the rest atrophy.

human reproduction

Approximately 12 days before the onset of Graafian menstruation, the vesicle bursts and the egg cell, together with the follicular cells surrounding it, is thrown into the abdominal cavity, from which it first enters the funnel of the oviduct, and then, thanks to the movements of the ciliated hairs, into the oviduct and into the uterus.

This process is called ovulation (Fig. 31).

The corpus luteum of pregnancy reaches a size of 2 cm or more and leaves behind a scar for a long time. If fertilization does not occur, then the corpus luteum atrophies after 10-12 days and is absorbed by phagocytes (periodic corpus luteum), after which a new ovulation occurs.

The egg implanted in the wall of the uterine mucosa, together with the torn parts of the mucosa, is removed with a blood stream.

The female reproductive system is a reproductive system and shows functional activity only at a certain (childbearing) age.

The optimal age for the implementation of the childbearing function is 20-40 years old, when the woman's body is perfectly prepared for conception, bearing, giving birth and feeding a child.

The period of puberty, the actual reproductive period, lasts about 30 years, from 15-17 to 45-47 years.

During this period, the entire reproductive system functions in a stable mode, which ensures the continuation of the family. In a healthy woman, during the reproductive period, all cycles are ovulatory, and 350-400 eggs are maturing throughout. Unlike other functional systems of the human body, the reproductive system is active upon reaching physical, intellectual, psycho-emotional and social maturity, upon reaching the optimal age for conceiving, bearing, giving birth and feeding a child.

The formation and extinction of the reproductive system occurs according to the same mechanisms, but in reverse order. Initially, during puberty, secondary sexual characteristics appear as a manifestation of steroigenesis in the ovaries (thelarche - 10-12 years, pubarche - 11-12 years, adre - six months before the first menstruation). Then menstruation appears, while at first the menstrual cycle is anovulatory, then ovulatory cycles with insufficiency of the luteal phase appear, and, finally, a mature, reproductive type of functioning of the entire system is established.

male reproductive system

The male sex gland is the testicle (testicle), which has the shape of a somewhat compressed ellipsoid.

The testicles are the place where the process of spermatogenesis takes place, resulting in the formation of spermatozoa.

Outside, the testis is covered with a fibrous membrane, from the inner surface of which, along the posterior edge, a proliferation of connective tissue is wedged into it.

From this expansion, thin connective tissue crossbars diverge, which divide the gland into 200-300 lobules. The lobules are distinguished: seminiferous tubules; intermediate connective tissue.

The wall of the convoluted tubules consists of two types of cells: those that form spermatozoa and those that participate in the nutrition of developing spermatozoa.

Spermatozoa enter the epididymis through the direct and efferent tubules, and from it into the vas deferens. The epididymis has a head, a body and a tail. In the epididymis, spermatozoa mature and become motile. From the epididymis, the vas deferens leaves, which, together with the vessels, is called the spermatic cord.

The prostate gland is an unpaired organ that is located under the bladder, covering its neck and forming part of the muscular sphincter of the bladder.

The shape of the prostate gland resembles a chestnut. It is a muscular-glandular organ. The prostate gland has a membrane, from which the septa extend deep into the septum, dividing the gland into lobules. The lobules of the prostate gland contain glandular tissue that produces prostate secretions.

This secret flows through the ducts into the urethra and forms the liquid part of the semen. The prostate gland (prostate) finally develops around the age of 17. Its mass in an adult is 17-28 g.

The male penis is the organ through which the urethra passes. It serves to expel urine outside and to perform sexual intercourse.

In the back, it is attached to the pubic bones, followed by the body of the penis and ends with the head, in which the neck of the head is distinguished - the narrower part, and the crown of the head - the wider part. The skin on the penis is thin, easily mobile, forming a fold on the anterior section, which is able to cover the head. On the head, the skin passes into the mucous membrane. Internally, the penis consists of three bodies.

Below is a spongy body through which the urethra passes, opening with an opening on the head, from above the right and left cavernous bodies. During sexual arousal, the cavernous bodies fill with blood, due to which the penis increases in size, becomes hard (an erection occurs), which allows you to have sexual intercourse and deliver sperm to the woman's cervix.

Pages:12next →

The structure of the human reproductive system

In order for parenthood to be responsible, so that desired and healthy children appear, every modern person must know how to maintain their reproductive health:

The optimal age for having children is 20-35 years.

It has been proven that if pregnancy occurs earlier or later, then it proceeds with a large number of complications and the likelihood of health problems in the mother and child is higher;

Abortion is the most unsafe method of birth control, it can be avoided with the help of modern methods of contraception;

If an unwanted pregnancy still occurs and the woman decides to have an abortion, you should consult a doctor as soon as possible - this will reduce the risk of possible complications during and after the abortion;

After childbirth and abortion, you can become pregnant before the arrival of the first menstruation, so it is necessary to choose a reliable method of contraception before the resumption of sexual activity;

· sexually transmitted infections often cause infertility in men and women;

Contraception makes intimate life more harmonious, eliminates unnecessary worries and anxieties.

The state of reproductive health is largely determined by a person's lifestyle, as well as a responsible attitude towards sexual life.

In turn, all this affects the stability of family relationships, the general well-being of a person.

The foundations of reproductive health are laid in childhood and adolescence.

The human reproductive system: role, reproductive organs and diseases

There is an opinion: everything connected with the birth of a future life depends entirely on the health of the future mother.

Actually it is not. It has been proven that out of 100 childless couples, 40-60% do not have children due to male infertility, which is associated with sexually transmitted infections, the impact on the male reproductive health of harmful environmental factors, working conditions and bad habits. These facts convincingly prove the importance of careful attitude to the reproductive health of not only the future woman, but also the man.

Reproductive system of a woman

The organs of the female reproductive system are the ovaries, fallopian tubes, uterus, vagina (Fig.

29). The reproductive system is a delicate mechanism that carries out a periodic process called the menstrual cycle. It is the menstrual cycle that creates on the part of the woman the prerequisites for the reproduction of offspring.

The main process of the menstrual cycle is the maturation of an egg capable of fertilization. In parallel, the mucous layer of the uterus (endometrium) is being prepared for the adoption of a fertilized egg (implantation). In order for both processes to occur in the desired sequence, hormones exist.

29. Organs of the female reproductive system

The process of egg formation - oogenesis (ovogenesis) and the synthesis of female sex hormones occurs in female gonads- ovaries. The ovaries vary in size, shape, and mass depending on age and individuality. In a woman who has reached puberty, the ovary looks like a thickened ellipsoid weighing from 5 to 8 g. The right ovary is somewhat larger than the left. In a newborn girl, the mass of the ovary is approximately 0.2 g.

At 5 years old, the weight of each ovary is 1 g, at 8-10 years old - 1.5 g, at 16 years old - 2 g. The ovary consists of 2 layers: cortical and cerebral. In the cortical layer, eggs are formed (Fig. 30).

Rice. 30. Human egg

The medulla is made up of connective tissue containing blood vessels and nerves. Female egg cells are formed from primary egg germ cells - oogonia, which, together with nourishing cells - follicular - form primary egg follicles.

Each egg follicle is a small egg cell surrounded by a row of flat follicular cells. In newborn girls, they are numerous and almost adjacent to each other, and in old age they disappear. In a 22-year-old healthy girl, 400,000 primary follicles can be found in both ovaries. During life, only 500 primary follicles mature and produce eggs capable of fertilization, while the rest atrophy.

Follicles reach their full development during puberty, from about 13 to 15 years of age, when some mature follicles secrete the hormone estrone.

The period of puberty (puberty) lasts in girls from 13 - 14 to 18 years.

Under the influence of FSH of the pituitary gland in the ovarian follicles, the maturation of the egg occurs.

Maturation consists in an increase in the size of the egg. Follicular cells multiply intensively and form several layers. The growing follicle begins to sink deep into the cortical layer, is surrounded by a fibrous connective tissue membrane, filled with fluid and enlarges, turning into a Graafian vesicle.

In this case, the egg with the surrounding follicular cells is pushed to one side of the bubble. A mature Graafian vesicle adjoins the very surface of the ovary.

Approximately 12 days before the onset of Graafian menstruation, the vesicle bursts and the egg cell, together with the follicular cells surrounding it, is thrown into the abdominal cavity, from which it first enters the funnel of the oviduct, and then, thanks to the movements of the ciliated hairs, into the oviduct and into the uterus. This process is called ovulation (Fig.

Rice. 31. Ovum maturation

If the egg is fertilized, it attaches to the wall of the uterus (implantation occurs) and the embryo begins to develop from it.

After ovulation, the wall of the Graafian vesicle collapses and in its place a temporary endocrine gland, the corpus luteum, forms on the surface of the ovary.

The corpus luteum hormone - progesterone prepares the uterine mucosa for the implantation of a fertilized egg, stimulates the development of the mammary glands and the muscular layer of the uterus. It regulates the normal course of pregnancy in its initial stages (up to 3-4 months).

The corpus luteum of pregnancy reaches a size of 2 cm or more and leaves behind a scar for a long time. If fertilization does not occur, then the corpus luteum atrophies after 10-12 days and is absorbed by phagocytes (periodic corpus luteum), after which a new ovulation occurs. The egg implanted in the wall of the uterine mucosa, together with the torn parts of the mucosa, is removed with a blood stream.

The first menstruation appears after the maturation of the first egg, the bursting of the Graafian vesicle and the development of the corpus luteum.

The menstrual cycle begins in a girl at 12-13 years old and ends at 50-53 years old, while the ability to bear children appears by 15-16 years old and the ovaries cease to function actively at 40-45 years old (Fig. 32).

Rice. 32. Ovarian-menstrual cycle of a woman

On average, the sexual cycle lasts 28 days and is divided into 4 periods:

1) restoration of the mucous membrane of the uterus within 7 - 8 days, or a period of rest;

2) proliferation of the uterine mucosa and its increase within 7-8 days, or preovulation, caused by increased secretion of the pituitary folliculotropic hormone and estrogen;

3) secretory - secretion, rich in mucus and glycogen, in the uterine mucosa, corresponding to the maturation and rupture of the Graafian vesicle, or ovulation;

4) rejection, or post-ovulation, lasting an average of 3-5 days, during which the uterus contracts tonically, its mucous membrane is torn off in small pieces and 50-150 ml of blood is released.

The last period occurs only in the absence of fertilization.

Cyclic processes associated with the maturation of the egg, are reflected in the physical performance of women.

In the ovulation period, as well as on the eve of menstruation, sports performance decreases. Maximum physical performance is noted in the pre- and post-ovulation period.

The female reproductive system is a reproductive system and shows functional activity only at a certain (childbearing) age. The optimal age for the implementation of the childbearing function is 20-40 years old, when the woman's body is perfectly prepared for conception, bearing, giving birth and feeding a child.

In the life of a woman, several age periods are distinguished, which differ significantly from each other: the intrauterine period, the period of childhood, the period of puberty, the mature reproductive period, the premenopausal period, perimenopause and postmenopause.

Unlike other functional systems of the body, the activity of the reproductive system is maintained only at a certain age, which is optimal for the implementation of the basic functions of the reproductive system: conception, bearing, giving birth, and feeding a child.

The period of puberty, the actual reproductive period, lasts about 30 years, from 15-17 to 45-47 years. During this period, the entire reproductive system functions in a stable mode, which ensures the continuation of the family.

In a healthy woman, during the reproductive period, all cycles are ovulatory, and 350-400 eggs are maturing throughout. Unlike other functional systems of the human body, the reproductive system is active upon reaching physical, intellectual, psycho-emotional and social maturity, upon reaching the optimal age for conceiving, bearing, giving birth and feeding a child.

This age is 20-40 years.

The formation and extinction of the reproductive system occurs according to the same mechanisms, but in reverse order.

Initially, during puberty, secondary sexual characteristics appear as a manifestation of steroigenesis in the ovaries (thelarche - 10-12 years, pubarche - 11-12 years, adre - six months before the first menstruation). Then menstruation appears, while at first the menstrual cycle is anovulatory, then ovulatory cycles with insufficiency of the luteal phase appear, and, finally, a mature, reproductive type of functioning of the entire system is established.

When the reproductive system is turned off, depending on age or on various stress agents, ovulatory cycles first appear with hypofunction of the corpus luteum, then anovulation develops, and with severe inhibition of the reproductive system, amenorrhea occurs.

The reproductive system (PC) is active at five functional levels, the adequate interaction of which ensures the maintenance of steroid-producing and generative functions.

male reproductive system

The male reproductive system is a set of male internal and external genital organs located in the lower part of the abdominal cavity and outside, in the lower abdomen (Fig.

33). The male reproductive organs are represented by the penis and gonads: testes, vas deferens, prostate and seminal vesicles.

male gonad is the testicle (testicle), having the shape of a somewhat compressed ellipsoid. The testicles are the place where the process of spermatogenesis takes place, resulting in the formation of spermatozoa.

In addition, male sex hormones are synthesized in the testes. In an adult, the weight in middle age is approximately 20-30 g. In children 8-10 years old - 0.8 g; 12-14 years old - 1.5 g; 15 years - 7 g. The testicles grow intensively up to 1 year and from 10 to 15 years.

Outside, the testis is covered with a fibrous membrane, from the inner surface of which, along the posterior edge, a proliferation of connective tissue is wedged into it. From this expansion, thin connective tissue crossbars diverge, which divide the gland into 200-300 lobules.

The lobules are distinguished: seminiferous tubules; intermediate connective tissue.

Rice. 33. Reproductive system of a man.

The wall of the convoluted tubules consists of two types of cells: those that form spermatozoa and those that participate in the nutrition of developing spermatozoa. Spermatozoa enter the epididymis through the direct and efferent tubules, and from it into the vas deferens.

The epididymis has a head, a body and a tail. In the epididymis, spermatozoa mature and become motile. From the epididymis, the vas deferens leaves, which, together with the vessels, is called the spermatic cord.

Above the prostate gland, both vas deferens pass into the vas deferens, which enter this gland, penetrate it and open into the urethra.

Prostate- This is an unpaired organ that is located under the bladder, covering its neck and forming part of the muscular sphincter of the bladder.

The shape of the prostate gland resembles a chestnut. It is a muscular-glandular organ. The prostate gland has a membrane, from which the septa extend deep into the septum, dividing the gland into lobules. The lobules of the prostate gland contain glandular tissue that produces prostate secretions. This secret flows through the ducts into the urethra and forms the liquid part of the semen. The prostate gland (prostate) finally develops around the age of 17.

Its mass in an adult is 17-28 g.

male penis is the organ through which the urethra passes. It serves to expel urine outside and to perform sexual intercourse. In the back, it is attached to the pubic bones, followed by the body of the penis and ends with the head, in which the neck of the head is distinguished - the narrower part, and the crown of the head - the wider part. The skin on the penis is thin, easily mobile, forming a fold on the anterior section, which is able to cover the head.

On the head, the skin passes into the mucous membrane. Internally, the penis consists of three bodies. Below is a spongy body through which the urethra passes, opening with an opening on the head, from above the right and left cavernous bodies. During sexual arousal, the cavernous bodies fill with blood, due to which the penis increases in size, becomes hard (an erection occurs), which allows you to have sexual intercourse and deliver sperm to the woman's cervix.

During ejaculation (ejaculation), due to muscle contraction, spermatozoa are released outward through the vas deferens and urethra. Each portion of semen contains 300-400 million spermatozoa. This large number is necessary because only a few hundred sperm actually reach the egg in the fallopian tube. Spermatozoa have a head, neck and tail (Fig.

Rice. 34. The structure of the sperm.

The head of the spermatozoon contains the father's genetic material.

In case of successful fertilization, it is he who determines the sex of the child (Fig. 35).

Rice. 35. Determination of the sex of the child.

The neck of the spermatozoon is a kind of battery that supplies energy for the movement of the spermatozoon.

The "motor" is the tail of the spermatozoon. Due to movements in different directions, which, like a whip, the tail makes, the spermatozoon moves forward.

Intrasecretory functions of the female and male gonads

Before puberty, male and female sex hormones are formed in approximately equal amounts in girls and boys. By the time of puberty, girls produce several times more female sex hormones than boys.

In young men, the secretion of male sex hormones increases. Premature puberty is inhibited by the thymus (goiter) gland. It functions as an endocrine until puberty.

In the female glands - the ovaries - estrogens are synthesized, as well as a small amount of testosterone, which is a precursor of estrogens.

Progesterone, the female sex hormone, is synthesized by the corpus luteum of the ovary, which is formed and carries out its functional activity after the onset of ovulation. Female sex hormones - estrogens(estrol, estriol and estradiol) act as regulators of the ovarian-menstrual cycle, and when pregnancy occurs, they regulate its normal course. Estrogens affect:

The development of the genital organs

The production of eggs

determine the preparation of the eggs for fertilization, the uterus - for pregnancy, the mammary glands - for feeding the child;

regulate the formation of the female figure and features of the skeleton;

Provide intrauterine development at all stages.

In addition, estrogens increase the synthesis of glycogen in the liver and the deposition of fat in the body.

Estrogens, getting from the ovaries into the blood, are transported throughout the body with the help of carrier proteins.

Estrogens are broken down in the liver by liver enzymes and excreted in the urine. Progesterone or corpus luteum hormone is synthesized in the ovaries and placenta during pregnancy. It helps to maintain pregnancy, prepares the inner mucosa of the uterus for implantation of a fertilized egg, suppresses the action of estrogen and uterine contraction, promotes the development of glandular tissue of the mammary glands, and under its influence, the basal temperature rises. Progesterone is broken down in the liver and excreted in the urine.

In addition, a certain amount of androgens is produced in the ovaries.

Just like in women, the regulation of reproductive function in men is carried out by hormones.

The highest authority is the brain, which controls the release of FSH and LH into the blood. Both hormones regulate the processes in the testicles. For example, FSH is mainly involved in the regulation of sperm maturation. LH stimulates the production of the male hormone testosterone.

male sex hormones androgens(testosterone, androstenediol, etc.) are formed in Leydig cells located in the interstitial tissue of the testes, as well as in the spermatogenic epithelium.

Testosterone and its derivative androsterone cause:

The development of the reproductive apparatus and the growth of the genital organs;

The development of secondary sexual characteristics: coarsening of the voice, change in physique, the appearance of hair on the face and body;

· affect the level of protein and carbohydrate metabolism, for example, reduce the synthesis of glycogen in the liver.

Androgens and estrogens, interacting with other hormones, affect bone growth, practically stopping it.

The development of the gonads

The gonads develop from a single embryonic germ at the 5th week of intrauterine development. Sexual differentiation occurs at the 7-8th week of the embryonic period of development.

male gonads.

Male gonads begin to produce testosterone at the end of the 3rd month of intrauterine life. At the 11-17th week, the level of androgens in the male fetus reaches the values ​​characteristic of an adult organism. Due to this, the development of the genital organs occurs according to the male pattern.

The weight of the testicle in a newborn is 0.3 g. Its hormonally producing activity is reduced. Under the influence of GnRH from the age of 12-13, it gradually grows and by the age of 16-17 reaches the level of adults.

The rise in hormone-producing activity causes a pubertal growth spurt, the appearance of secondary sexual characteristics, and after 15 years, activation of spermatogenesis.

Female gonads. Starting from the 20th week of the intrauterine period, the formation of primordial follicles occurs in the ovary. Estrogens begin to be synthesized towards the end of the prenatal period. Ovarian hormones do not affect the formation of the genital organs, it occurs under the influence of maternal gonadotropic hormones, placental estrogens and fetal adrenal glands.

In newborn girls, during the first 5-7 days, maternal hormones circulate in the blood, then their concentration decreases. By the time of birth, the mass of the ovary is 5-6 g, in an adult woman it is 6-8 g. At the beginning of postnatal ontogenesis, three periods of activity are distinguished in the ovary: neutral (from birth to 6-7 years), prepubertal (from 8 years to the first menstruation) , puberty (from the moment of the first menstruation to menopause). At all stages, follicular cells produce estrogens in varying amounts.

A low level of estrogen up to 8 years creates the possibility of differentiation of the hypothalamus according to the female type. Estrogen production in puberty is already sufficient for the puberty jump (skeletal growth, as well as for the development of secondary sexual characteristics). Gradually, an increase in estrogen production leads to menarche and the formation of a regular menstrual cycle.

The human body is a complex of physiological systems (nervous, cardiovascular, respiratory, digestive, excretory, etc.) that ensure the existence of a person as an individual. Violation of any of them leads to disorders, often incompatible with life. The functions of the reproductive or reproductive system are primarily aimed at the continuation of the existence of man as a biological species. All life-supporting systems function from the moment of birth to death, the reproductive "works" only in a certain age period, corresponding to the optimal rise in physiological capabilities. This temporal conditionality is associated with biological expediency - the bearing and rearing of offspring requires significant resources of the body. Genetically, this period is programmed for the age of 18–45 years.

Reproductive function is a complex of processes that covers the differentiation and maturation of germ cells, the process of fertilization, pregnancy, childbirth, lactation and subsequent care of offspring. Interaction and regulation of these processes are provided by the system, the center of which is the neuroendocrine complex: hypothalamus - pituitary gland - gonads. The central role in the implementation of the reproductive function is played by the reproductive, or genital, organs. The reproductive organs are divided into internal and external.

The structure and age features of the male reproductive system

In men, the internal genital organs include the gonads (testicles with appendages), the vas deferens, the vas deferens, the seminal vesicles, the prostate, and the bulbourethral (Cooper) glands; to the external genital organs - the scrotum and penis (Fig. 9.2).

Fig. 9.2.

Testicle - a paired male sex gland that performs exo- and endocrine functions in the body. The testicles produce spermatozoa (external secretion) and sex hormones that influence the development of primary and secondary sexual characteristics (internal secretion). In shape, the testicle (testis) is an oval, slightly compressed laterally body, lying in the scrotum. The right testicle is larger, heavier and located higher than the left.

The testicles are formed in the abdominal cavity of the fetus and before birth (at the end of pregnancy) descend into the scrotum. The movement of the testicles occurs along the so-called inguinal canal - an anatomical formation that serves to conduct the testicles to the scrotum, and after the completion of the lowering process - to locate the vas deferens. The testicles, having passed the inguinal canal, descend to the bottom of the scrotum and are fixed there by the time the child is born. Undescended testicle (cryptorchidism) leads to a violation of its thermal regime, blood supply, trauma, which contributes to the development of dystrophic processes in it and requires medical intervention.

In a newborn, the length of the testicle is 10 mm, the weight is 0.4 g. Before puberty, the testicle grows slowly, and then its development accelerates. By the age of 14, it has a length of 20-25 mm and a weight of 2 g. At 18-20 years old, its length is 38-40 mm, weight - 20 g. Later, the size and weight of the testicle increase slightly, and after 60 years, slightly decrease.

The testicle is covered with a dense connective tissue membrane, which forms a thickening at the posterior edge, called mediastinum. From the mediastinum inside the testicle, radially located connective tissue septa extend, which divide the testis into many lobules (100–300). Each lobule includes 3–4 closed convoluted seminiferous tubules, connective tissue, and interstitial Leydig cells. Leydig cells produce male sex hormones, and the spermatogenic epithelium of the seminiferous tubules produce spermatozoa, consisting of a head, neck and tail. The convoluted seminiferous tubules pass into the direct seminiferous tubules, which open into the ducts of the testicular network located in the mediastinum. In a newborn, the convoluted and straight seminiferous tubules do not have a lumen - it appears by puberty. In adolescence, the diameter of the seminiferous tubules doubles, and in adult men it triples.

The efferent tubules (15–20) emerge from the network of the testis, which, strongly wriggling, form cone-shaped structures. The combination of these structures is an appendage of the testicle, adjacent to the upper pole and the posterolateral edge of the testicle, in which the head, body, and tail are distinguished. The epididymis of a newborn is large, its length is 20 mm, its weight is 0.12 g. During the first 10 years, the epididymis grows slowly, and then its growth accelerates.

In the region of the body of the appendage, the efferent tubules merge into the duct of the appendage, which passes into the region of the tail into vas deferens , which contains mature but immobile spermatozoa, has a diameter of about 3 mm and reaches a length of 50 cm. Its wall consists of mucous, muscular and connective tissue membranes. At the level of the lower pole of the testicle, the vas deferens turns upward and, as part of the spermatic cord, which also includes vessels, nerves, membranes and the muscle that lifts the testicle, follows the inguinal canal into the abdominal cavity. There it separates from the spermatic cord and, without passing through the peritoneum, descends into the small pelvis. Near the bottom of the bladder, the duct expands, forming an ampulla, and, having accepted the excretory ducts of the seminal vesicles, continues as ejaculatory duct. The latter passes through the prostate gland and opens into the prostatic part of the urethra.

In a child, the vas deferens is thin, its longitudinal muscle layer appears only by the age of 5. The muscle that lifts the testicle is poorly developed. The diameter of the spermatic cord in a newborn is 4.5 mm, at 15 years old - 6 mm. The spermatic cord and vas deferens grow slowly until the age of 14–15, and then their growth accelerates. Spermatozoa, mixing with the secretion of the seminal vesicles and the prostate gland, acquire the ability to move and form seminal fluid (sperm).

seminal vesicles are a paired oblong organ about 4-5 cm long, located between the bottom of the bladder and the rectum. They produce a secret that is part of the seminal fluid. The seminal vesicles of a newborn are poorly developed, with a small cavity, only 1 mm long. Up to 12–14 years old, they grow slowly, at 13–16 years old, growth accelerates, the size and cavity increase. At the same time, their position also changes. In a newborn, the seminal vesicles are located high (due to the high position of the bladder) and are covered on all sides by the peritoneum. By the age of two, they descend and lie retroperitoneally.

prostate (prostate) ) is located in the pelvic area under the bottom of the bladder. Its length in an adult man is 3 cm, weight - 18-22 g. The prostate consists of glandular and smooth muscle tissues. The glandular tissue forms lobules of the gland, the ducts of which open into the prostate part of the urethra. Prostate mass in a newborn

0.82 g, at 3 years old - 1.5 g, after 10 years there is an accelerated growth of the gland and by the age of 16 its mass reaches 8–10 g. The shape of the gland in a newborn is spherical, since the lobules are not yet expressed, it is located high, has a soft texture, glandular tissue is absent in it. By the end of the pubertal period, the internal opening of the urethra shifts to its anterior superior edge, the glandular parenchyma and prostate ducts are formed, the gland acquires a dense texture.

bulbourethral (Cooper's) gland - a paired organ the size of a pea - located in the urogenital diaphragm. Its function is to secrete a mucous secretion that promotes the movement of sperm through the urethra. Its excretory duct is very thin, 3-4 cm long, opens into the lumen of the urethra.

Scrotum is a receptacle for testicles and appendages. In a healthy man, it is reduced due to the presence in its walls of muscle cells - myocytes. The scrotum is like a "physiological thermostat" that maintains the temperature of the testicles at a lower level than the body temperature. This is a necessary condition for the normal development of spermatozoa. In a newborn, the scrotum is small in size, its intensive growth is observed during puberty.

Penis has a head, neck, body and root. The head is the thickened end of the penis, on which the external opening of the urethra opens. Between the head and the body of the penis there is a narrowed part - the neck. The root of the penis is attached to the pubic bones. The penis consists of three cavernous bodies, two of which are called the cavernous bodies of the penis, the third - the spongy body of the urethra (the urethra passes through it). The anterior part of the spongy body is thickened and forms the head of the penis. Each cavernous body is covered on the outside with a dense connective tissue membrane, and inside it has a spongy structure: thanks to numerous partitions, small cavities ("caves") are formed, which fill with blood during intercourse, the penis swells and comes into a state of erection. The length of the penis in a newborn is 2-2.5 cm, the foreskin is long and completely covers its head (phimosis). In children of the first years of life, the state of phimosis is physiological, however, with a pronounced narrowing, swelling of the foreskin can be noted, leading to difficulty urinating. A whitish sebaceous substance (smegma) accumulates under the foreskin, produced by glands located on the glans penis. If personal hygiene is not followed and infection is added, smegma decomposes, causing inflammation of the head and foreskin.

Before puberty, the penis grows slowly, and then its growth accelerates.

Spermatogenesis - the process of development of male germ cells, ending with the formation of spermatozoa. Spermatogenesis begins under the influence of sex hormones during the puberty of a teenager and then proceeds continuously, and in most men - almost until the end of life.

The process of sperm maturation occurs inside the convoluted seminiferous tubules and lasts an average of 74 days. On the inner wall of the tubules are spermatogonia (the earliest, first cells of spermatogenesis), containing a double set of chromosomes. After a series of successive divisions, in which the number of chromosomes in each cell is halved, and after a long phase of differentiation, spermatogonia turn into spermatozoa. This happens by gradual elongation of the cell, changing and elongating its shape, as a result of which the cell nucleus forms the head of the spermatozoon, and the membrane and cytoplasm form the neck and tail. Each spermatozoon carries a half set of chromosomes, which, when combined with a female germ cell, will give a complete set necessary for the development of the embryo. After that, mature spermatozoa enter the lumen of the testicular tubule and further into the epididymis, where they are accumulated and excreted from the body during ejaculation. 1 ml of semen contains up to 100 million spermatozoa.

A mature, normal human spermatozoon consists of a head, neck, body, and tail, or flagellum, which ends in a thin terminal filament (Fig. 9.3). The total length of the spermatozoon is about 50–60 µm (head 5–6 µm, neck and body 6–7 µm, and tail 40–50 µm). In the head is the nucleus, which carries the paternal hereditary material. At its anterior end is the acrosome, which ensures the penetration of the sperm through the membranes of the female egg. Mitochondria and spiral filaments are located in the neck and body, which are the source of the motor activity of the spermatozoon. An axial filament (axoneme) departs from the neck through the body and tail, surrounded by a sheath, under which 8–10 smaller filaments are located around the axial filament - fibrils that perform motor or skeletal functions in the cell. Motility is the most characteristic property of the spermatozoon and is carried out with the help of uniform blows of the tail by rotating around its own axis in a clockwise direction. The duration of the existence of the sperm in the vagina reaches 2.5 hours, in the cervix - 48 hours or more. Normally, the spermatozoon always moves against the flow of fluid, which allows it to move up at a speed of 3 mm / min along the female genital tract until it meets the egg.

How long does a man remain fertile? It is not possible to give an unambiguous answer to this question. Childbearing age depends on many factors. In some men, the ability to conceive remains until old age, but in most it fades by the age of 60. It is possible to predict the childbearing age of a particular man, but only if it is known exactly how this subject was sexually formed.

From a medical point of view, the average young man becomes fertile at 14 years of age and retains the ability to conceive up to 60 years. However, this does not mean at all that a young man should become a father before the age of 20. The best period for the birth of children in a man is 25-45 years. At this time, the man is most active and his sexual functions have not yet begun to fade.

How does a man mature?

As mentioned above, in a teenager, reproductive function is turned on at 14 years of age. But the development of his reproductive system does not stop there. Next, the teenager goes through a series of periods that affect his reproductive abilities.

The first physiological changes in the reproductive system begin to occur in boys at the age of 10-12. The first sexual feelings for the opposite sex appear. sex drive goes through 3 stages of development:

1. The emergence of interest in girls.
2. The desire to hold the girl by the hand, touch her, kiss her.
3. The appearance of sexual arousal.

Initially, boys are not interested in the immediate physiology of relationships due to low reproductive capacity. Interest in her comes at the 3rd stage of the development of sexual desire.

As you go through all the stages of puberty, a young man produces testosterone. This hormone stimulates the development of sexual characteristics and reproductive function. It also makes a young man fertile and interesting to the opposite sex.

Time of first sexual contact depends on the social environment in which the young man is brought up and lives. Often, due to misconceptions about male sexuality, teenagers see sex as the main goal of a relationship with a girl, and this is wrong. Because of this, young families often break up.

By the age of 25, a man yearns for more sensual relationships. He consciously seeks to start a family. But this doesn't happen to everyone. There are men who prefer to remain free both in relationships and in sex.

According to surveys, it is only after reaching adulthood that most men begin to experience true pleasure from sex with their wives. This is explained by the fact that over the years the couple has learned the sensual secrets of each other. As a result, emotional coloring is mixed with physical satisfaction.

Changes in male sexual behavior with age

The reproductive age of a man largely depends on his sexual activity. Eg, man is 100% fertile, but avoids communication with women due to unwillingness to have children. In this case, we can say that its reproductive function does not work. The reluctance to start a family can stay with him for life.

At the same time, one should take into account the fact that the reproductive age directly depends on the physiological age. After the age of 35, a man's need for sex drops sharply. The thing is that less and less testosterone is being produced in his body. Plus emotional experiences in the family and stress. All this leads to the fact that his sex is no longer interested. That is, after 35 years, reproductive functions fade.

It should also be borne in mind that over the age of 35 spermatogenesis worsens. Spermatozoa not only become less active, their genetic properties deteriorate.

Socially, a man is best of years to start a family by the age of 35. Surprisingly, the same age is best suited for the birth of a child. But in psychological terms, young people are best prepared for starting a family at the age of 25.

How does age affect fertility?

Among women the deadline for having children is 40 years. The fact is that after this age the opportunity to give birth to a healthy child is greatly reduced. In men, everything is more uncertain, since there is practically no research in this regard.

The French made an attempt to change the situation. Scientists from this country studied a sample of documents of 10,000 couples who were treated for infertility. The researchers managed to find out that if men have overcome the milestone of 35 years, then it is more difficult for their wives to bear a child. There is a high chance of miscarriages. By the age of 40, the likelihood of conceiving a child is significantly reduced.

The results of this scientific work cause serious concern among physicians, since in recent decades the average age of men who become fathers for the first time has exceeded 35 years.

How to support reproductive function?

If the decline in fertility is not caused by diseases, then you can resort to the following recommendations:

If these measures do not help, then don't be afraid to see a doctor.

The male reproductive system includes the scrotum, testicles, seminal ducts, gonads, and penis. These organs work together to produce sperm, male gametes, and other components of sperm. These organs also work together to carry sperm out of the body and into the vagina, where it will help fertilize the egg to produce offspring… [Read below]

• Lower torso

[Start from above] … Scrotum
The scrotum is a burso-like organ made of skin and muscle that houses the testes. It is located lower than the penis in the pubic region. The scrotum consists of 2 testis sacs located side by side. The smooth muscles that make up the scrotum allow them to regulate the distance between the testes and the rest of the body. When the testicles become too warm to support spermatogenesis, the scrotum relaxes to move the testicles away from heat sources. Conversely, the scrotum moves closer to the body with the testicles when the temperature drops below the ideal range for spermatogenesis.

testicles

The 2 testes, also known as the testicles, are the male gonads responsible for the production of sperm and testosterone. The testicles are ellipsoidal glandular organs about 4 to 5 cm long and 3 cm in diameter. Each testis resides inside its own sac on one side of the scrotum and is connected to the abdomen by the funiculus and cremaster muscle. Internally, the testicles are divided into small compartments known as lobules. Each lobule contains a section of seminiferous tubules lined with epithelial cells. These epithelial cells contain many stem cells that divide and form sperm through the process of spermatogenesis.

Appendages

The epididymis is a sperm storage area that wraps around the superior and posterior margins of the testicles. The appendage consists of several long, thin tubes that are tightly coiled into a small mass. Spermatozoa are produced in the testicles and pass into the adnexa to mature before being passed through the male reproductive organs. The length of the appendage delays the release of spermatozoa and gives them time to mature.

spermatic cord and vas deferens

In the scrotum, a pair of spermatic cords connects the testes to the abdominal cavity. The spermatic cords contain the vas deferens along with the nerves, veins, arteries, and lymphatics that support the function of the testes.
The vas deferens is a muscular tube that carries semen from the epididymis into the abdominal cavity to the ejaculatory canal. The vas deferens is wider in diameter than the epididymis and uses its internal space to store mature sperm. The smooth muscles of the walls of the vas deferens are used to move sperm to the ejaculatory duct through the peristalsis.

seminal vesicles

The seminal vesicles are a pair of lumpy exocrine glands that store and produce some of the liquid semen. The seminal vesicles are about 5 cm long and are located behind the bladder closer to the rectum. The fluid in the seminal vesicles contains proteins and phlegm and has an alkaline pH to help sperm survive the acidic environment of the vagina. The liquid also contains fructose to feed the sperm cells so they survive long enough to fertilize an egg.

Ejaculatory canal

The vas deferens passes through the prostate and joins the urethra at a structure known as the ejaculatory duct. The ejaculatory canal also contains canals from the seminal vesicles. During ejaculation, the ejaculatory canal opens and expels semen and secretions from the seminal vesicles into the urethra.

Urethra

Sperm travels from the ejaculatory canal to the outside of the body through the urethra, a 20 to 25 cm long muscular tube. The urethra passes through the prostate and ends at the external opening of the urethra, located at the end of the penis. Urine exiting the body, from the bladder, passes through the urethra.

The walnut-sized prostate gland borders the lower end of the bladder and surrounds the urethra. The prostate produces most of the fluid, which is semen. This liquid is milky white in color and contains enzymes, proteins and other chemicals to support and protect sperm during ejaculation. The prostate also contains smooth muscle tissue that can contract to prevent the flow of urine or semen.

cooper glands
Cooper's glands, also known as bulbourethral glands, are a pair of pea-sized exocrine glands located below the prostate and up to the anus. Cooper's glands secrete a thin, alkaline fluid into the urethra, which lubricates the urethra and neutralizes acid from the urine that remains in the urethra after urination. This fluid enters the urethra during sexual arousal prior to ejaculation to prepare the urethra for the flow of semen.

Penis
The penis is the male external sex organ located above the scrotum and below the navel. The penis is roughly cylindrical and contains the urethra and the external opening of the urethra. Large pockets of erectile tissue in the penis allow it to fill with blood and become erect. Excitation of the penis leads to its increase in size. The function of the penis is to deliver semen to the vagina during intercourse. In addition to its reproductive function, the penis also allows urine to pass through the urethra to the outside of the body.

Sperm
Sperm is the fluid produced by males for sexual reproduction and ejected from the body during intercourse. Sperm contains spermatozoa, the male sex gametes, along with a range of chemicals suspended in a fluid medium. The chemical makeup of semen gives it a thick, sticky texture and a slightly alkaline pH. These traits help sperm maintain reproduction by helping sperm stay in the vagina after intercourse and to neutralize the acidic environment of the vagina. In healthy adult males, semen contains about 100 million sperm per milliliter. These sperm cells fertilize the oocytes inside the female fallopian tubes.

spermatogenesis

Spermatogenesis is the process of sperm production that occurs in the testicles and appendages of adult males. Before puberty, there is no spermatogenesis due to the lack of hormonal triggers. During puberty, spermatogenesis begins when enough luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are produced. LH initiates the production of testosterone by the testicles, while FSH causes the maturation of germ cells. Testosterone stimulates stem cells in the testes, known as spermatogonia. Each diploid spermatocyte goes through the process of meiosis I and splits into 2 haploid secondary spermatocytes. Secondary spermatocytes go through meiosis II to form 4 haploid spermatids of the cell. The spermatids of the cell go through a process known as spermatogenesis, where they grow a flagellum and develop a sperm head structure. After spermatogenesis, the cell finally turns into spermatozoa. The spermatozoa are ejected into the appendages, where they complete their maturation and become able to move on their own.

Fertilization

Fertilization is the process by which a sperm combines with oocytes or eggs to become a fertilized zygote. The sperm released during ejaculation must first swim through the vagina and uterus into the fallopian tubes, where they can find an egg. Having collided with the egg, the sperm must penetrate the layers of the oocyte. Sperm cells contain enzymes in the acrosomal region of the head, which allows them to penetrate these layers. Once inside the oocyte, the nuclei of these cells fuse to form diploid cells known as the zygote. The zygote cell begins cell division to form an embryo.