What are the main parts of the male genital anatomy. How does the penis function during sexual arousal and urination. What common conditions can affect the penis and how are they diagnosed and treated.

The Anatomy of the Male Penis: A Comprehensive Overview

The penis, a crucial component of the male reproductive system, serves dual functions: sexual reproduction and urination. Its structure is complex, comprising several distinct parts that work in harmony to fulfill these roles. Let’s delve into the intricate anatomy of this organ to better understand its function and potential health concerns.

Key Components of the Penis

• Glans (head) of the penis
• Corpus cavernosum
• Corpus spongiosum
• Urethra
• Foreskin (in uncircumcised men)

The glans, or head of the penis, is covered by a layer of moist tissue called mucosa in uncircumcised men. This mucosa is protected by the foreskin, which is surgically removed in circumcised individuals, causing the glans to develop a layer of dry skin.

Running along the sides of the penis are two columns of tissue known as the corpus cavernosum. These structures play a vital role in the erectile process. The corpus spongiosum, another column of sponge-like tissue, runs along the front of the penis and terminates at the glans. It surrounds the urethra, the tube through which urine and semen exit the body.

The Physiology of Erections: How Does the Penis Become Erect?

An erection is a complex physiological process involving the nervous system, blood vessels, and penile tissues. When a man becomes sexually aroused, the brain sends signals via nerves to the penis, initiating a series of events:

1. Blood vessels in the penis dilate
2. Blood flow into the penis increases
3. Blood outflow from the penis decreases
4. The corpus cavernosum fills with blood, causing the penis to become rigid
5. The corpus spongiosum also fills with blood, keeping the urethra open

This process results in the enlargement and hardening of the penis, preparing it for sexual intercourse. The duration and quality of an erection can be affected by various factors, including age, health conditions, and lifestyle choices.

Common Penis Conditions: Symptoms, Causes, and Implications

The penis can be affected by numerous conditions, ranging from minor irritations to serious medical issues. Understanding these conditions is crucial for maintaining penile health and overall well-being.

Erectile Dysfunction (ED)

Erectile dysfunction occurs when a man is unable to achieve or maintain an erection sufficient for satisfactory sexual performance. While occasional difficulties are normal, persistent ED can significantly impact quality of life and may indicate underlying health problems.

The most common cause of ED is atherosclerosis, a condition characterized by the buildup of plaque in the arteries, which can restrict blood flow to the penis. Other potential causes include:

• Diabetes
• Hypertension
• Hormonal imbalances
• Neurological disorders
• Psychological factors (e.g., stress, anxiety, depression)

Priapism: A Painful Emergency

Priapism is a potentially serious condition characterized by a prolonged and often painful erection that persists even in the absence of sexual stimulation. This condition requires immediate medical attention to prevent long-term damage to the penile tissues.

Congenital and Acquired Penile Abnormalities

Several conditions can affect the structure and function of the penis from birth or develop later in life:

• Hypospadias: A birth defect where the urethral opening is located on the underside of the penis rather than at the tip
• Chordee: An abnormal curvature of the penis present from birth
• Peyronie’s Disease: An acquired condition causing abnormal curvature of the penis shaft, often due to injury or other medical conditions
• Micropenis: An abnormally small penis present from birth, often associated with hormonal imbalances

Infections and Inflammatory Conditions of the Penis

The penis is susceptible to various infections and inflammatory conditions that can cause discomfort and require medical intervention.

Balanitis and Balanoposthitis

Balanitis refers to inflammation of the glans penis, often resulting from infection. When this inflammation also involves the foreskin in uncircumcised men, it is termed balanoposthitis. Symptoms may include pain, tenderness, and redness of the penis head.

Sexually Transmitted Infections (STIs)

Several STIs can affect the penis, including:

• Gonorrhea: Caused by N. gonorrhea bacteria, often resulting in painful urination and discharge
• Chlamydia: A bacterial infection that may be asymptomatic in up to 40% of cases
• Syphilis: Characterized by a painless ulcer (chancre) on the penis in its initial stage
• Herpes: Viral infection causing recurring blisters and ulcers on the penis
• Human Papillomavirus (HPV): Can cause genital warts on the penis

Diagnostic Procedures for Penis-Related Conditions

Accurate diagnosis is crucial for effective treatment of penile conditions. Healthcare providers may employ various diagnostic techniques:

Physical Examination and Medical History

A thorough physical examination of the penis and surrounding areas, combined with a detailed medical history, forms the foundation of diagnosis for many penile conditions.

Laboratory Tests

• Urethral swab: Samples from the urethra are cultured to identify infections
• Urinalysis: Examines urine for signs of infection, bleeding, or kidney problems
• Urine culture: Helps diagnose urinary tract infections that may affect the penis
• Polymerase Chain Reaction (PCR): A sensitive test that can detect various organisms affecting the penis

Specialized Tests

For specific conditions, particularly erectile dysfunction, specialized tests may be necessary:

• Nocturnal penile tumescence testing: Measures erections during sleep to help identify the cause of ED
• Doppler ultrasound: Assesses blood flow in the penis
• Hormone tests: Evaluate levels of testosterone and other hormones that may affect penile function

Treatment Options for Penis-Related Conditions

The treatment of penile conditions varies widely depending on the specific diagnosis. Here are some common approaches:

Medications

• Phosphodiesterase inhibitors (e.g., sildenafil, tadalafil): Enhance blood flow to the penis, improving erectile function
• Antibiotics: Treat bacterial infections such as gonorrhea, chlamydia, and syphilis
• Antiviral medications: Suppress outbreaks of herpes and other viral infections
• Testosterone replacement therapy: May improve erectile function in men with low testosterone levels

Surgical Interventions

In some cases, surgery may be necessary to correct structural abnormalities or treat severe conditions:

• Hypospadias repair: Corrects the position of the urethral opening
• Circumcision: Removal of the foreskin, which may be recommended for certain conditions
• Penile implants: Surgical insertion of devices to enable erections in cases of severe ED
• Cancer surgery: Removal of cancerous tissue in cases of penile cancer

Preventive Measures and Maintaining Penile Health

Maintaining good penile health is essential for overall well-being and sexual function. Here are some key preventive measures:

Hygiene Practices

• Regular washing with mild soap and water
• Thorough drying after bathing or swimming
• For uncircumcised men, careful cleaning beneath the foreskin

Safe Sex Practices

• Consistent use of condoms to prevent STIs
• Regular STI testing, especially with new partners
• Open communication with sexual partners about sexual health

Lifestyle Factors

• Maintaining a healthy diet and regular exercise routine
• Avoiding excessive alcohol consumption and quitting smoking
• Managing stress through relaxation techniques or counseling

By understanding the anatomy and function of the penis, recognizing potential health issues, and adopting preventive measures, men can maintain optimal penile health throughout their lives. Regular check-ups with healthcare providers and prompt attention to any unusual symptoms are key to addressing potential problems early and ensuring long-term sexual and urinary health.

As medical knowledge advances, new treatments and preventive strategies for penile health continue to emerge. Staying informed about these developments and maintaining open communication with healthcare providers can help men make informed decisions about their penile health and overall well-being.

Remember, many penile conditions are treatable, and seeking timely medical attention can prevent complications and improve outcomes. Don’t hesitate to consult a healthcare professional if you experience any concerning symptoms or have questions about your penile health.

Diagram, Function, Conditions, and More

Human Anatomy

Written by Matthew Hoffman, MD

• Image Source
• Penis Conditions
• Penis Tests
• Penis Treatments

© 2014 WebMD, LLC. All rights reserved.

The penis is the male sex organ, reaching its full size during puberty. In addition to its sexual function, the penis acts as a conduit for urine to leave the body.

The penis is made of several parts:
• Glans (head) of the penis: In uncircumcised men, the glans is covered with pink, moist tissue called mucosa. Covering the glans is the foreskin (prepuce). In circumcised men, the foreskin is surgically removed and the mucosa on the glans transforms into dry skin.
• Corpus cavernosum: Two columns of tissue running along the sides of the penis. Blood fills this tissue to cause an erection.
• Corpus spongiosum: A column of sponge-like tissue running along the front of the penis and ending at the glans penis; it fills with blood during an erection, keeping the urethra — which runs through it — open.
• The urethra runs through the corpus spongiosum, conducting urine out of the body.

An erection results from changes in blood flow in the penis. When a man becomes sexually aroused, nerves cause penis blood vessels to expand. More blood flows in and less flows out of the penis, hardening the tissue in the corpus cavernosum.

• Erectile dysfunction: A man’s penis does not achieve sufficient hardness for satisfying intercourse. Atherosclerosis (damage to the arteries) is the most common cause of erectile dysfunction.
• Priapism: An abnormal erection that does not go away after several hours even though stimulation has stopped. Serious problems can result from this painful condition.
• Hypospadias: A birth defect in which the opening for urine is on the front (or underside), rather than the tip of the penis. Surgery can correct this condition.
• Phimosis (paraphimosis): The foreskin cannot be retracted or if retracted cannot be returned to its normal position over the penis head. In adult men, this can occur after penis infections.
• Balanitis: Inflammation of the glans penis, usually due to infection. Pain, tenderness, and redness of the penis head are symptoms.
• Balanoposthitis: Balanitis that also involves the foreskin (in an uncircumcised man).
• Chordee: An abnormal curvature of the end of the penis, present from birth. Severe cases may require surgical correction.
• Peyronie’s Disease: An abnormal curvature of the shaft of the penis may be caused by injury of the adult penis or other medical conditions.
• Urethritis: Inflammation or infection of the urethra, often causing pain with urination and penis discharge. Gonorrhea and chlamydia are common causes.
• Gonorrhea: The bacteria N. gonorrhea infects the penis during sex, causing urethritis. Most cases of gonorrhea in men cause symptoms of painful urination or discharge.
• Chlamydia: A bacteria that can infect the penis through sex, causing urethritis. Up to 40% of chlamydia cases in men cause no symptoms.
• Syphilis: A bacteria transmitted during sex. The initial symptom of syphilis is usually a painless ulcer (chancre) on the penis.
• Herpes: The viruses HSV-1 and HSV-2 can cause small blisters and ulcers on the penis that reoccur over time.
• Micropenis: An abnormally small penis, present from birth. A hormone imbalance is involved in many cases of micropenis.
• Penis warts: The human papillomavirus (HPV) can cause warts on the penis. HPV warts are highly contagious and spread during sexual contact.
• Cancer of the penis: Penis cancer is very rare in the U.S. Circumcision decreases the risk of penis cancer.

• Urethral swab: A swab of the inside of the penis is sent for culture. A urethral swab may diagnose urethritis or other infections.
• Urinalysis: A test of various chemicals present in urine. A urinalysis may detect infection, bleeding, or kidney problems.
• Nocturnal penis tumescence testing (erection testing): An elastic device worn on the penis at night can detect erections during sleep. This test can help identify the cause of erectile dysfunction.
• Urine culture: Culturing the urine in the lab can help diagnose a urinary tract infection that might affect the penis.
• Polymerase chain reaction (PCR): A urine test that can detect gonorrhea, chlamydia, or other organisms that affect the penis.

• Phosphodiesterase inhibitors: These medicines (such as sildenafil or Viagra) enhance the flow of blood to the penis, making erections harder.
• Antibiotics: Gonorrhea, chlamydia, syphilis, and other bacterial infections of the penis can be cured with antibiotics.
• Antiviral medicines: Taken daily, medicines to suppress HSV can prevent herpes outbreaks on the penis.
• Penis surgery: Surgery can correct hypospadias, and may be necessary for penis cancer.
• Testosterone: Low testosterone by itself rarely causes erectile dysfunction. Testosterone supplements may improve erectile dysfunction in some men.

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Human Reproductive Anatomy | Biology for Majors II

Describe human male and female reproductive anatomies

As animals became more complex, specific organs and organ systems developed to support specific functions for the organism. The reproductive structures that evolved in land animals allow males and females to mate, fertilize internally, and support the growth and development of offspring.

The reproductive tissues of male and female humans develop similarly in utero until a low level of the hormone testosterone is released from male gonads. Testosterone causes the undeveloped tissues to differentiate into male sexual organs. When testosterone is absent, the tissues develop into female sexual tissues. Primitive gonads become testes or ovaries. Tissues that produce a penis in males produce a clitoris in females. The tissue that will become the scrotum in a male becomes the labia in a female; that is, they are homologous structures.

Learning Objectives

• Describe human male reproductive anatomies
• Describe human female reproductive anatomies
• Discuss the human sexual response
• Discuss the differences and similarities between spermatogenesis and oogenesis

Male Reproductive Anatomy

Figure 1.  The reproductive structures of the human male are shown.

In the male reproductive system, the scrotum houses the testicles or testes (singular: testis), including providing passage for blood vessels, nerves, and muscles related to testicular function. The testes are a pair of male reproductive organs that produce sperm and some reproductive hormones. Each testis is approximately 2.5 by 3.8 cm (1.5 by 1 in) in size and divided into wedge-shaped lobules by connective tissue called septa. Coiled in each wedge are seminiferous tubules that produce sperm.

Sperm are immobile at body temperature; therefore, the scrotum and penis are external to the body, as illustrated in Figure 1 so that a proper temperature is maintained for motility. In land mammals, the pair of testes must be suspended outside the body at about 2^° C lower than body temperature to produce viable sperm. Infertility can occur in land mammals when the testes do not descend through the abdominal cavity during fetal development.

Practice Question

Which of the following statements about the male reproductive system is false?

1. The vas deferens carries sperm from the testes to the penis.
2. Sperm mature in seminiferous tubules in the testes.
3. Both the prostate and the bulbourethral glands produce components of the semen.
4. The prostate gland is located in the testes.

Show Answer

Sperm mature in seminiferous tubules that are coiled inside the testes, as illustrated in Figure 1. The walls of the seminiferous tubules are made up of the developing sperm cells, with the least developed sperm at the periphery of the tubule and the fully developed sperm in the lumen. The sperm cells are mixed with “nursemaid” cells called Sertoli cells which protect the germ cells and promote their development. Other cells mixed in the wall of the tubules are the interstitial cells of Leydig. These cells produce high levels of testosterone once the male reaches adolescence.

When the sperm have developed flagella and are nearly mature, they leave the testicles and enter the epididymis, shown in Figure 1. This structure resembles a comma and lies along the top and posterior portion of the testes; it is the site of sperm maturation. The sperm leave the epididymis and enter the vas deferens (or ductus deferens), which carries the sperm, behind the bladder, and forms the ejaculatory duct with the duct from the seminal vesicles. During a vasectomy, a section of the vas deferens is removed, preventing sperm from being passed out of the body during ejaculation and preventing fertilization.

Semen is a mixture of sperm and spermatic duct secretions (about 10 percent of the total) and fluids from accessory glands that contribute most of the semen’s volume. Sperm are haploid cells, consisting of a flagellum as a tail, a neck that contains the cell’s energy-producing mitochondria, and a head that contains the genetic material. Figure 2 shows a micrograph of human sperm as well as a diagram of the parts of the sperm. An acrosome is found at the top of the head of the sperm. This structure contains lysosomal enzymes that can digest the protective coverings that surround the egg to help the sperm penetrate and fertilize the egg. An ejaculate will contain from two to five milliliters of fluid with from 50–120 million sperm per milliliter.

Figure 2. Human sperm, visualized using scanning electron microscopy, have a flagellum, neck, and head. (credit b: modification of work by Mariana Ruiz Villareal; scale-bar data from Matt Russell)

The bulk of the semen comes from the accessory glands associated with the male reproductive system. These are the seminal vesicles, the prostate gland, and the bulbourethral gland, all of which are illustrated in Figure 1. The seminal vesicles are a pair of glands that lie along the posterior border of the urinary bladder. The glands make a solution that is thick, yellowish, and alkaline. As sperm are only motile in an alkaline environment, a basic pH is important to reverse the acidity of the vaginal environment. The solution also contains mucus, fructose (a sperm mitochondrial nutrient), a coagulating enzyme, ascorbic acid, and local-acting hormones called prostaglandins. The seminal vesicle glands account for 60 percent of the bulk of semen.

The penis, illustrated in Figure 1, is an organ that drains urine from the renal bladder and functions as a copulatory organ during intercourse. The penis contains three tubes of erectile tissue running through the length of the organ. These consist of a pair of tubes on the dorsal side, called the corpus cavernosum, and a single tube of tissue on the ventral side, called the corpus spongiosum. This tissue will become engorged with blood, becoming erect and hard, in preparation for intercourse. The organ is inserted into the vagina culminating with an ejaculation. During intercourse, the smooth muscle sphincters at the opening to the renal bladder close and prevent urine from entering the penis. An orgasm is a two-stage process: first, glands and accessory organs connected to the testes contract, then semen (containing sperm) is expelled through the urethra during ejaculation. After intercourse, the blood drains from the erectile tissue and the penis becomes flaccid.

The walnut-shaped prostate gland surrounds the urethra, the connection to the urinary bladder. It has a series of short ducts that directly connect to the urethra. The gland is a mixture of smooth muscle and glandular tissue. The muscle provides much of the force needed for ejaculation to occur. The glandular tissue makes a thin, milky fluid that contains citrate (a nutrient), enzymes, and prostate specific antigen (PSA). PSA is a proteolytic enzyme that helps to liquefy the ejaculate several minutes after release from the male. Prostate gland secretions account for about 30 percent of the bulk of semen.

The bulbourethral gland, or Cowper’s gland, releases its secretion prior to the release of the bulk of the semen. It neutralizes any acid residue in the urethra left over from urine. This usually accounts for a couple of drops of fluid in the total ejaculate and may contain a few sperm. Withdrawal of the penis from the vagina before ejaculation to prevent pregnancy may not work if sperm are present in the bulbourethral gland secretions. The location and functions of the male reproductive organs are summarized in Table 1.

Female Reproductive Anatomy

A number of reproductive structures are exterior to the female’s body. These include the breasts and the vulva, which consists of the mons pubis, clitoris, labia majora, labia minora, and the vestibular glands, all illustrated in Figure 3. The location and functions of the female reproductive organs are summarized in Table 2. The vulva is an area associated with the vestibule which includes the structures found in the inguinal (groin) area of women. The mons pubis is a round, fatty area that overlies the pubic symphysis. The clitoris is a structure with erectile tissue that contains a large number of sensory nerves and serves as a source of stimulation during intercourse. The labia majora are a pair of elongated folds of tissue that run posterior from the mons pubis and enclose the other components of the vulva. The labia majora derive from the same tissue that produces the scrotum in a male. The labia minora are thin folds of tissue centrally located within the labia majora. These labia protect the openings to the vagina and urethra. The mons pubis and the anterior portion of the labia majora become covered with hair during adolescence; the labia minora is hairless. The greater vestibular glands are found at the sides of the vaginal opening and provide lubrication during intercourse.

Figure 3. The reproductive structures of the human female are shown. (credit a: modification of work by Gray’s Anatomy; credit b: modification of work by CDC)

The breasts consist of mammary glands and fat. The size of the breast is determined by the amount of fat deposited behind the gland. Each gland consists of 15 to 25 lobes that have ducts that empty at the nipple and that supply the nursing child with nutrient- and antibody-rich milk to aid development and protect the child.

Internal female reproductive structures include ovaries, oviducts, the uterus, and the vagina, shown in Figure 3. The pair of ovaries is held in place in the abdominal cavity by a system of ligaments. Ovaries consist of a medulla and cortex: the medulla contains nerves and blood vessels to supply the cortex with nutrients and remove waste. The outer layers of cells of the cortex are the functional parts of the ovaries. The cortex is made up of follicular cells that surround eggs that develop during fetal development in utero. During the menstrual period, a batch of follicular cells develops and prepares the eggs for release. At ovulation, one follicle ruptures and one egg is released, as illustrated in Figure 4a.

Figure 4. Oocytes develop in (a) follicles, located in the ovary. At the beginning of the menstrual cycle, the follicle matures. At ovulation, the follicle ruptures, releasing the egg. The follicle becomes a corpus luteum, which eventually degenerates. The (b) follicle in this light micrograph has an oocyte at its center. (credit a: modification of work by NIH; scale-bar data from Matt Russell)

The oviducts, or fallopian tubes, extend from the uterus in the lower abdominal cavity to the ovaries, but they are not in contact with the ovaries. The lateral ends of the oviducts flare out into a trumpet-like structure and have a fringe of finger-like projections called fimbriae, illustrated in Figure 4b. When an egg is released at ovulation, the fimbrae help the non-motile egg enter into the tube and passage to the uterus. The walls of the oviducts are ciliated and are made up mostly of smooth muscle. The cilia beat toward the middle, and the smooth muscle contracts in the same direction, moving the egg toward the uterus. Fertilization usually takes place within the oviducts and the developing embryo is moved toward the uterus for development. It usually takes the egg or embryo a week to travel through the oviduct. Sterilization in women is called a tubal ligation; it is analogous to a vasectomy in males in that the oviducts are severed and sealed.

The uterus is a structure about the size of a woman’s fist. This is lined with an endometrium rich in blood vessels and mucus glands. The uterus supports the developing embryo and fetus during gestation. The thickest portion of the wall of the uterus is made of smooth muscle. Contractions of the smooth muscle in the uterus aid in passing the baby through the vagina during labor. A portion of the lining of the uterus sloughs off during each menstrual period, and then builds up again in preparation for an implantation. Part of the uterus, called the cervix, protrudes into the top of the vagina. The cervix functions as the birth canal.

The vagina is a muscular tube that serves several purposes. It allows menstrual flow to leave the body. It is the receptacle for the penis during intercourse and the vessel for the delivery of offspring. It is lined by stratified squamous epithelial cells to protect the underlying tissue.

Sexual Response

The sexual response in humans is both psychological and physiological. Both sexes experience sexual arousal through psychological and physical stimulation. There are four phases of the sexual response. During phase one, called excitement, vasodilation leads to vasocongestion in erectile tissues in both men and women. The nipples, clitoris, labia, and penis engorge with blood and become enlarged. Vaginal secretions are released to lubricate the vagina to facilitate intercourse. During the second phase, called the plateau, stimulation continues, the outer third of the vaginal wall enlarges with blood, and breathing and heart rate increase.

During phase three, or orgasm, rhythmic, involuntary contractions of muscles occur in both sexes. In the male, the reproductive accessory glands and tubules constrict placing semen in the urethra, then the urethra contracts expelling the semen through the penis. In women, the uterus and vaginal muscles contract in waves that may last slightly less than a second each. During phase four, or resolution, the processes described in the first three phases reverse themselves and return to their normal state. Men experience a refractory period in which they cannot maintain an erection or ejaculate for a period of time ranging from minutes to hours.

Gametogenesis

Gametogenesis, the production of sperm and eggs, takes place through the process of meiosis. During meiosis, two cell divisions separate the paired chromosomes in the nucleus and then separate the chromatids that were made during an earlier stage of the cell’s life cycle. Meiosis produces haploid cells with half of each pair of chromosomes normally found in diploid cells. The production of sperm is called spermatogenesis and the production of eggs is called oogenesis.

Spermatogenesis

Spermatogenesis, illustrated in Figure 5, occurs in the wall of the seminiferous tubules, with stem cells at the periphery of the tube and the spermatozoa at the lumen of the tube. Immediately under the capsule of the tubule are diploid, undifferentiated cells. These stem cells, called spermatogonia (singular: spermatagonium), go through mitosis with one offspring going on to differentiate into a sperm cell and the other giving rise to the next generation of sperm.

Figure 5. During spermatogenesis, four sperm result from each primary spermatocyte.

Meiosis starts with a cell called a primary spermatocyte. At the end of the first meiotic division, a haploid cell is produced called a secondary spermatocyte. This cell is haploid and must go through another meiotic cell division. The cell produced at the end of meiosis is called a spermatid and when it reaches the lumen of the tubule and grows a flagellum, it is called a sperm cell. Four sperm result from each primary spermatocyte that goes through meiosis.

Stem cells are deposited during gestation and are present at birth through the beginning of adolescence, but in an inactive state. During adolescence, gonadotropic hormones from the anterior pituitary cause the activation of these cells and the production of viable sperm. This continues into old age.

Visit this site to see the process of spermatogenesis.

Oogenesis

Figure 6. The process of oogenesis occurs in the ovary’s outermost layer.

Oogenesis, illustrated in Figure 6, occurs in the outermost layers of the ovaries. As with sperm production, oogenesis starts with a germ cell, called an oogonium (plural: oogonia), but this cell undergoes mitosis to increase in number, eventually resulting in up to about one to two million cells in the embryo.

The cell starting meiosis is called a primary oocyte, as shown in Figure 6. This cell will start the first meiotic division and be arrested in its progress in the first prophase stage. At the time of birth, all future eggs are in the prophase stage. At adolescence, anterior pituitary hormones cause the development of a number of follicles in an ovary. This results in the primary oocyte finishing the first meiotic division. The cell divides unequally, with most of the cellular material and organelles going to one cell, called a secondary oocyte, and only one set of chromosomes and a small amount of cytoplasm going to the other cell. This second cell is called a polar body and usually dies. A secondary meiotic arrest occurs, this time at the metaphase II stage. At ovulation, this secondary oocyte will be released and travel toward the uterus through the oviduct. If the secondary oocyte is fertilized, the cell continues through the meiosis II, producing a second polar body and a fertilized egg containing all 46 chromosomes of a human being, half of them coming from the sperm.

Egg production begins before birth, is arrested during meiosis until puberty, and then individual cells continue through at each menstrual cycle. One egg is produced from each meiotic process, with the extra chromosomes and chromatids going into polar bodies that degenerate and are reabsorbed by the body.

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Anatomy of the genital organs and urogenital system of men and women

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Before proceeding to the analysis of various diseases directly, it seems necessary to say a few words about anatomy – the structure of those organs that urology studies. Life has shown that people’s knowledge on this subject leaves much to be desired.

Urinary system

Diagram of the urogenital system

The urinary system is almost the same in men and women. It starts with the kidney. The kidney is an organ slightly smaller than a fist, dark brown in color, shaped like a bean.

The main function of the kidneys is to produce urine. Large blood vessels approach the kidneys, and the blood, as it were, is filtered through the kidney, while various harmful substances are retained in it. This is how urine is formed. A person has two kidneys, they are located in the lumbar region. Kidney disease is often manifested by lower back pain on the right or left.

A narrow tube descends from each kidney – the ureter. It carries urine to the bladder. The lumen of the ureter is 4-6 mm, the length is about 30 cm. Both ureters flow into the bladder.

Bladder is the place where urine collects before it is expelled from the body. The human bladder is one, it is located in the lower abdomen behind the pubis. Depending on the amount of urine, the bladder can expand and contract. In total, the bladder in different people can hold from 250 to 500 ml of urine. With the maximum filling of the bladder, a person feels an acute urge to urinate. Two ureters enter the bladder. The lower part of the bladder narrows and gradually passes into the urethra.

This opening can be squeezed and opened by a person to control urination. The narrowed part is called the neck of the bladder.

The urethra begins from the bladder. It serves to excrete urine. The urethra differs in men and women – in men it is long and narrow (20-40 cm long, about 8 mm wide), and in women it is short and wide (3-4 cm long, 1-1.5 cm wide). With inflammation of the urethra, pain and cramps appear in it during urination, which is especially evident in men, and in women it often goes unnoticed.

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Male Reproductive System

Male Pelvic Diagram

Male Reproductive System – at least if not more important branch of urology. It includes the testicles and their appendages, the spermatic cord, seminal vesicles, the prostate gland, some small glands and the penis.

Testis – an organ that produces spermatozoa and testosterone – the male sex hormone. A spermatozoon is a cell with a tail, similar to a tadpole. The task of this cell is to get into the female body and merge with the female egg, which leads to conception. Every minute, 50,000 new spermatozoa are produced in the testicles.

. The scrotum regulates the temperature in the testicles and protects them from injury. The left testicle in most men is larger than the right one and is located slightly lower.

The epididymis is a short, thick tube with an irregular surface. Passing through it, the spermatozoa mature and acquire their main quality – mobility.

A long, narrow tube extends from the epididymis, surrounded by blood vessels. The tube is called the vas deferens, and together with the vessels – the spermatic cord. The spermatic cord goes from the scrotum to the inguinal canal, which is located in the inguinal fold, then bends and approaches the neck of the bladder. Each testicle has its own spermatic cord. Its main purpose is the removal from the testicles and the promotion of mature spermatozoa.

The vas deferens, approaching the neck of the bladder, expand and form the seminal vesicles. They accumulate spermatozoa and store them until they are excreted from the body. The seminal vesicles empty into the urethra.

Under the bladder is a very important formation – the prostate gland (prostate). It is about the size of a medium chestnut. It encircles the neck of the bladder and the very beginning of the urethra. The seminal vesicles pass through the prostate before entering the urethra. This gland produces a special secretion that mixes with spermatozoa and, as a result, forms sperm. Thus, sperm enters the urethra.

Structure of the male penis

Male penis – an organ that serves to perform sexual intercourse and makes fertilization possible. The penis consists of three bodies. Above are the right and left cavernous bodies of the penis, and below them is the spongy body through which the urethra passes.

Ruslan Ivanovich Solomenny

Urologist, ultrasound specialist

Experience in medical practice since 2011.

Zaseda Yuri Igorevich

Andrologist, sexologist, urologist, reproductive specialist, psychotherapist.

More than 31 years of experience in medical practice.

Doctor of the highest category. Doctor of Medical Sciences. Founder and chief physician of the clinic.

Andrology

Andrology deals with the study of male anatomy, physiology, pathologies of the male genital area, methods of their treatment.

What andrology treats

The male reproductive system consists of the prostate gland, scrotum with testicles and appendages, seminal ducts, seminal vesicles, penis. The male reproductive system works for the formation of sperm fluid, the production of male sex hormones, the implementation of sexual intercourse, and the excretion of sperm.

An andrologist deals with the study of the physiology of the male body, diseases of the male reproductive system, methods of their treatment, malformations of the male genital area, injuries of the male reproductive organs, helps men fight infertility.

Andrology works closely with endocrinology, venereology, sexology, dermatology, vascular and plastic surgery. Diagnosis, prevention, treatment of diseases and social adaptation are a wide range of duties of an andrologist.

Andrology has several directions in the treatment of male pathologies:

• reproductive direction – infertility treatment,
• sexual disorders – premature ejaculation, low libido, impotence,
• reconstructive surgery – reconstruction of the urethra,
• genital surgery – elimination of defects in the male genital organs (aesthetic),
• andropause – the onset of male menopause,
• oncoandrology,
• diseases of the prostate gland,
• andrological infectious diseases and sexually transmitted diseases,
• problems associated with gender reassignment.

Andrology – diagnosis and treatment of diseases in men

Diseases of the male genital area are divided into groups:

• inflammation of the male genital organs,
• pathology of the development of male genital organs,
• injuries of male genital organs,
• tumors of the genital organs of men.

Inflammatory processes of the male genital area

Inflammatory processes of the male genital area, which are studied and treated by andrology:

• inflammation of the testicles and their appendages (epididymitis, orchitis),
• inflammation of the urethra (urethritis),
• inflammation of the prostate gland (prostatitis),
• inflammation of the foreskin and glans penis (balanoposthitis).

Inflammatory processes in the genital area of ​​a man, if they are not treated in a timely manner, can spread to neighboring organs and tissues. Inflammatory processes are infectious and non-infectious. Unprotected sexual contacts, poor hygiene can provoke the development of infectious processes in the male genital organs. An allergic reaction, disorders that occurred during fetal development, trauma to the genital organs can affect the development of non-infectious inflammation. Infectious inflammations can be specific and nonspecific. Inflammatory processes can be caused by fungi, protozoa, viruses and bacteria. Inflammatory processes in the genital area of ​​a man often proceed hidden, they can be identified by an increase in ESR in the blood, complaints of general malaise, pain in the back, and genitals.

Infectious diseases of the male genital area include a number of diseases:

• AIDS,
• cytomegalovirus,
• hepatitis (C, B, D),
• candidiasis,
• trichomoniasis,
• herpes,
• venereal diseases.

Infection with trichomonads, mycoplasmosis proceeds latently, often without manifesting itself. Untreated diseases lead to male infertility. Reduced immunity, hormonal disruptions worsen the course of inflammatory processes. For any symptoms of trouble, you should seek qualified help from a specialist – an andrologist.

Symptoms of distress:
• pain in the perineum, lower abdomen, back,
• burning during urination, urinary incontinence, frequent urination,
• the presence of pus, blood in the urine, an unpleasant odor,
• decreased libido, impaired potency, erection,
• pain during intercourse,
• formations in the groin area – papillomas, condylomas, warts and others,
• infertility.

Andrologist, after examining and conducting a series of studies, prescribes treatment.

Tests ordered by an andrologist:

• urethral swab,
• blood and urine tests,
• secret of the prostate gland (analysis),
• Ultrasound of the pelvic organs,
• determination of prostate specific antigen,
• spermogram,
• test for erectile dysfunction,
• advice from other specialists, if required.

Andrologist’s methods of treatment are divided into certain types: conservative, surgical, prosthetics, circumcision. Conservative treatment involves the use of therapeutic methods of treatment. Surgical treatment is the use of surgery to restore the functioning of the male reproductive system, surgery for oncological diseases and prostate adenoma, treatment of varicocele using microsurgical surgery. Prosthetics of the penis and removal of the foreskin of the male penis are also carried out.

Infertility

Andrology researches and treats male infertility. There are two forms of male infertility – obstructive and secretory. The secretory form of infertility is a violation of the formation of spermatozoa, the obstructive form of infertility is the presence of an obstacle to the movement of spermatozoa to the urethra. Infertility in men can be immunological.

Secretory infertility

The testicles do not produce enough sperm for fertilization, spermatozoa may have impaired motility or have an abnormal morphological structure. Secretory infertility develops as a result of negative factors affecting the testicles.

Adverse factors affecting the male testicles include:

• varicose veins (varicocele),
• hydrocele,
• cryptorchidism,
• parotitis.

Varicocele is accompanied by dilation of the ovarian veins, the possibility of outflow of blood from the testicle decreases, blood stasis develops, blood supply and testicular function are disturbed due to the development of blood stasis. As a result, the quantitative and qualitative production of spermatozoa decreases. There are few spermatozoa in the semen and most of the spermatozoa have an irregular structure. A secretory form of infertility develops.

With dropsy of the testicle, fluid accumulates in the scrotum, which compresses the testicle. This condition is accompanied by a violation of the blood supply to the testicles, a decrease in the quality of sperm.

Undescended testes into the scrotum (cryptorchidism) causes testicular dysfunction. As a result of reduced function, secretory infertility develops.

When mumps is a disease, various glands of the body are affected. In boys, the testicles are affected by the virus. The inflammatory process in the testicles can cause a violation of their function, especially if the inflammation is not treated.

Various negative factors can affect the spermatogenic epithelium: electromagnetic oscillations, prolonged exposure to radiation, high temperatures. The same negative impact can be exerted by compression of the testicles, trauma to the testicles.

Various diseases lead to spermatogenic infertility: hormonal disorders, tuberculosis, syphilis, typhoid. Taking steroid drugs, antiandrogens, antibiotics, anticancer and antiepileptic drugs can impair testicular function and lead to spermatogenic infertility.

Obstructive form of infertility

Obstruction of the vas deferens can be caused by various reasons: inflammation of the epididymis (epididymitis), trauma, accidental damage during surgery on the pelvic organs – the rectum, bladder, ureters and other organs. The cause of obstruction may be a tumor of the epididymis, testicular cyst. Often, obstruction occurs due to a congenital defect – the absence of the vas deferens or epididymis. Tuberculosis and syphilis can cause complications in the form of obstruction of the vas deferens.