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Which process is needed to complete male reproductive development?

Which process is needed to complete male reproductive development?


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In order to properly complete male reproductive development:

A. primordial germ cells must begin Meiosis I in utero. B. Sertoli cells must produce testosterone. C. Dihydrotestosterone must masculinize Wolffian duct derivatives D. the paramesonephric ducts must degenerate E. the metanephros must form the genital epithelium

My attempt: I think the answer is C because testosterone turns into DHT which then masculinzing the wolffian duct. Other people I am studying with claim the answer is D (which is true) except that I dont think the loss of the paramesonephric duct is needed to complete male repro development.


Regarding option C:

Although it is correct that testosterone is converted into DHT, it is the former, not the latter, which is responsible for differentiation of the mesonephric (a.k.a. Wolffian) ducts:

Between 8 and 12 weeks, the initial secretion of testosterone stimulates mesonephric ducts to transform into a system of organs-the epididymis, vas deferens, and seminal vesicle-that connect the testes with the urethra.*

DHT (dihydrotestosterone) is produced in the Leydig cells by the 5α-Reductase enzyme. It is required for induction of the external male genitalia (urethra, penis, and scrotum) and prostate from the embryonic ureteral groove, and for testicular descent into scrotum.

Regarding option D:

Sertoli cells secrete Anti Müllerian Hormone (AMH), which causes degeneration of the müllerian (a.k.a. paramesonephric) ducts between weeks 8 and 10. It is normal to speak about degeneration of the müllerian ducts as a defining aspect of male embryology, and thus I believe answer D is correct. Your point is taken, however:

Nevertheless, small müllerian duct remnants can be detected in the adult male, including a small cap of tissue associated with the testis, called the appendix testis, and an expansion of the prostatic urethra, called the prostatic utricle.*


*Larsen's Human Embryology , Fourth Edition. Chapter 15: Development of the Urogenital System. pp 479-541. Copyright © 2009 by Churchill Livingstone, an imprint of Elsevier Inc.


The reproductive tissues of male and female humans develop similarly in utero until about the seventh week of gestation when a low level of the hormone testosterone is released from the gonads of the developing male. Testosterone causes the primitive gonads to differentiate into male sexual organs. When testosterone is absent, the primitive gonads develop into 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. Thus the male and female anatomies arise from a divergence in the development of what were once common embryonic structures.

Sperm are immobile at body temperature therefore, the testes are external to the body so that a correct temperature is maintained for motility. In land mammals, including humans, the pair of testes must be suspended outside the body so the environment of the sperm is about 2 °C lower than body temperature to produce viable sperm. If the testes do not descend through the abdominal cavity during fetal development, the individual has reduced fertility.

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

The penis drains urine from the urinary bladder and is a copulatory organ during intercourse (Figure 13.12 Table 13.1). The penis contains three tubes of erectile tissue that become engorged with blood, making the penis erect, in preparation for intercourse. The organ is inserted into the vagina culminating with an ejaculation. During orgasm, the accessory organs and glands connected to the testes contract and empty the semen (containing sperm) into the urethra and the fluid is expelled from the body by muscular contractions causing ejaculation. After intercourse, the blood drains from the erectile tissue and the penis becomes flaccid.

Semen is a mixture of sperm (about five 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 for motility, a neck that contains the cell’s energy-producing mitochondria, and a head that contains the genetic material (Figure 13.11). An acrosome (acrosomal vesicle) is found at the top of the head of the sperm. This structure contains enzymes that can digest the protective coverings that surround the egg and allow the sperm to fuse with the egg. An ejaculate will contain from two to five milliliters of fluid and from 50–120 million sperm per milliliter.

Figure 13.11 As seen in this scanning electron micrograph, human sperm has a flagellum, neck, and head. (credit: scale-bar data from Matt Russell)

Sperm form in the walls of seminiferous tubules that are coiled inside the testes (Figure 13.12 Table 13.1). 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 next to the lumen. The sperm cells are associated with Sertoli cells that nourish and promote the development of the sperm. Other cells present between the walls of the tubules are the interstitial cells of Leydig, which produce testosterone once the male reaches adolescence.

When the sperm have developed flagella they leave the seminiferous tubules and enter the epididymis (Figure 13.12 Table 13.1). This structure lies along the top and posterior of the testes and is the site of sperm maturation. The sperm leave the epididymis and enter the vas 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 (but not the secretions of the accessory glands) from being passed out of the body during ejaculation and preventing fertilization.

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 (Figure 13.12 Table 13.1). The secretions from the accessory glands provide important compounds for the sperm including nutrients, electrolytes, and pH buffering. There are also coagulation factors that affect sperm delivery and motility.

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

A. The vas deferens carries sperm from the testes to the seminal vesicles.

B. The ejaculatory duct joins the urethra.

C. Both the prostate and the bulbourethral glands produce components of the semen.

D. The prostate gland is located in the testes.

Table 13.1 Male Reproductive Anatomy
Organ Location Function
Scrotum External Supports testes and regulates their temperature
Penis External Delivers urine, copulating organ
Testes Internal Produce sperm and male hormones
Seminal Vesicles Internal Contribute to semen production
Prostate Gland Internal Contributes to semen production
Bulbourethtral Glands Internal Neutralize urine in urethra

Contents

Human male Edit

The male reproductive system contains two main divisions: the testes where sperm are produced, and the penis. In humans, both of these organs are outside the abdominal cavity. Having the testes outside the abdomen facilitates temperature regulation of the sperm, which require specific temperatures to survive about 2-3 °C less than the normal body temperature i.e. 37 °C. In particular, the extraperitoneal location of the testes may result in a 2-fold reduction in the heat-induced contribution to the spontaneous mutation rate in male germinal tissues compared to tissues at 37 °C. [1] If the testicles remain too close to the body, it is likely that the increase in temperature will harm the spermatozoa formation, making conception more difficult. This is why the testes are carried in an external pouch viz. scrotum rather than within the abdomen they normally remain slightly cooler than body temperature, facilitating sperm production.

Human female Edit

The female reproductive system likewise contains two main divisions: the vagina and the Ovum.

The ovum meets with sperm cell, a sperm may penetrate and merge with the egg, fertilizing it with the help of certain hydrolytic enzymes present in the acrosome. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then becomes implanted in the lining of the uterus, where it begins the processes of embryogenesis and morphogenesis. When the fetus is developed enough to survive outside of the uterus, the cervix dilates and contractions of the uterus propel it through the birth canal, which is the vagina.

The ova, which are the female sex cells, are much larger than the spermatozoon and are normally formed within the ovaries of the female fetus before its birth. They are mostly fixed in location within the ovary until their transit to the uterus, and contain nutrients for the later zygote and embryo. Over a, usually, regular interval known as the menstrual cycle, in response to hormonal signals, a process of oogenesis matures one ovum which is released and sent down the Fallopian tube. If not fertilized, this egg is flushed out of the system through menstruation.


6.6.6 Discuss the ethical issues associated with IVF.

Arguments for IVF

Arguments against IVF

Many types of infertility are due to environmental factors rather than genetic which means that the offspring would not inherit the infertility.

The infertility of the parents may be inherited by their offspring passing on the suffering to the next generation.

The embryos that are killed during the IVF process cannot feel pain or suffering as they do not have a developed nervous system.

More embryos are produced than needed and the ones that remain are usually killed which denies them the chance of a life.

Suffering caused by genetic diseases can be decreases by screening the embryos before placing them into the uterus.

Embryologists select which embryos will be placed into the uterus. Therefore they decide the fate of new individuals as they choose which ones will survive and which ones will die.

Since the IVF process is not an easy one emotionally and physically, is costly, takes time and there are no guarantees, parents who are willing to go through it must have a strong desire to have children and therefore are likely to be loving parents.

IVF is not a natural process which takes place in a laboratory compared to natural conception which occurs as a result of an act of love.

Infertility can cause emotional suffering to couples who want to have children. IVF can take away this suffering for some of those couples.

Infertility should be accepted as God&rsquos will and to go against it by using IVF procedures would be wrong.


Contents

Penis Edit

The penis is the male intromittent organ. It has a long shaft and an enlarged bulbous-shaped tip called the glans penis, which supports and is protected by the foreskin. When the male becomes sexually aroused, the penis becomes erect and ready for sexual activity. Erection occurs because sinuses within the erectile tissue of the penis become filled with blood. The arteries of the penis are dilated while the veins are compressed so that blood flows into the erectile cartilage under pressure. The penis is supplied by the pudendal artery.

Scrotum Edit

The scrotum is a pouch-like structure that hangs behind the penis. It holds and protects the testicles. It also contains numerous nerves and blood vessels. During times of lower temperatures, the Cremaster muscle contracts and pulls the scrotum closer to the body, while the Dartos muscle gives it a wrinkled appearance when the temperature increases, the Cremaster and Dartos muscles relax to bring down the scrotum away from the body and remove the wrinkles respectively.

The scrotum remains connected with the abdomen or pelvic cavity by the inguinal canal. (The spermatic cord, formed from spermatic artery, vein and nerve bound together with connective tissue passes into the testis through inguinal canal.)

Testis Edit

Testis has two major functions: To produce sperm by meiotic division of germ cells within the seminiferous tubules, [1] and to synthesize and secrete androgens that regulate the male reproductive functions. The site of production of androgens is the Leydig cells that are located in the interstitium between seminoferous tubules. [1]

Epididymis Edit

The epididymis is a long whitish mass of tightly coiled tube. The sperm that are produced in the seminiferous tubules flow into the epididymis. During passage via the epididymis, the sperm undergo maturation and are concentrated by the action of ion channels located on the apical membrane of the epididymis. [2]

Vas deferens Edit

The vas deferens, which is also known as the sperm duct, is a thin tube approximately 30 centimetres (0.98 ft) long that starts from the epididymis to the pelvic cavity. It carries the spermatozoa from the epididymis to ejaculatory duct.

Accessory glands Edit

Three accessory glands provide fluids that lubricate the duct system and nourish the sperm cells. They are the seminal vesicles, the prostate gland, and the bulbourethral glands (Cowper glands).

The embryonic and prenatal development of the male reproductive system is the process whereby the reproductive organs grow, mature and are established. It begins with a single fertilized egg and culminates 38 weeks later with birth of a male child. It is a part of the stages of sexual differentiation. The development of the male reproductive system coincides with the urinary system. The development of them can also be described together as the development of the urinary and reproductive organs.

Sexual determination Edit

Sexual identity is determined at fertilization when the genetic sex of the zygote has been initialized by a sperm cell containing either an X or Y chromosome. If this sperm cell contains an X chromosome it will coincide with the X chromosome of the ovum and a female child will develop. A sperm cell carrying a Y chromosome results in an XY combination, and a male child will develop. [3]

Genetic sex determines whether the gonads will be testes or ovaries. In the developing embryo if the testes are developed, it will produce and secrete male sex hormones during late embryonic development and cause the secondary sex organs of the male to develop. [4] [ clarification needed ]

Other embryonic reproductive structures Edit

The structures are masculinized by secretions of the testes:

The prostate gland derives from the urogenital sinus, and the other embryonic structures differentiate into the external genitalia. In the absence of testicular secretions, the female genitalia are formed. [7]

External structures Edit

At six weeks post conception, the differentiation of the external genitalia in the male and female has not taken place. At eight weeks, a distinct phallus is present during the indifferent stage. By the 10th-12th week, the genitalia are distinctly male or female being and derived from their homologous structures. At 16 weeks post conception, the genitalia are formed and distinct. [8] [9]

The masculinization of the embryonic reproductive structures occurs as a result of testosterone secreted by the embryonic testes. Testosterone, however, is not the active agent within these organs. Once inside the target cells, testosterone is converted by means of an enzyme called 5α-reductase into the dihydrotestosterone (DHT). DHT mediates the androgen effect in these organs. [10]

Testes Edit

At nine weeks, male differentiation of the gonads and the testes is well underway. Internal changes include the formation of the tubular seminar Chris tubules in the Rete testis from the primary sex cord. Developing on the outside surface of each testis is a Phibro muscular cord called the gubernaculum. This structure attaches to the inferior portion of the testis and extends to the labial sacral fold of the same side at the same time, a portion of the embryonic mesonephric duct adjacent to the testis becomes attached and convoluted informs the epididymis. Another portion of the mesonephric duct becomes the ductus deferens. [10]

The seminal vesicles form from lateral outgrowths of the caudal and of each mesonephric duct the prostate gland arises from an Indo dermal outgrowth of the urogenital sinus the bulbourethral glands develop from outgrowths in the membrane-like portion of the urethra. [10]

The descent of the testes to its final location at the anterior abdominal wall, followed by the development of the gubernaculum, which subsequently pulls and translocates the testis down into the developing scrotum. Ultimately, the passageway closes behind the testis. A failure in this process can cause indirect inguinal hernia or an infantile hydrocoele. [ citation needed ] The testes descend into the scrotal sac between the sixth and 10th week. Dissent into this not occur until about the 28th week when compared and we know canals form and the abdominal wall to provide openings from the pelvic cavity to the scrotal sac. The process by which a testis to send is not well understood but it seems to be associated with the shortening of the gubernaculum, which is attached to the testis and extends to the inguinal canal to the wall of the scrotum as a testis to sense it passes to the side of the urinary bladder and anterior to the symphysis pubis. It carries with it the ductus deference, that is testicular vessels and nerves, a portion of the abdominal muscle, and lymph vessels. All of the structures remain attached to the testis and form what is known as the spermatic cord by the time the testis is in the scrotal sac, the gubernaculum is no more than a remnant of scar like tissue. [10]

External genitalia Edit

The external genitalia of the male is distinct from those of the female by the end of the ninth week. Prior to that, the genital tubercle in both sexes is a phallus. The urethral groove forms on the ventral surface of the phallus early in development during the differentiation of the external genitalia. This is caused by the androgens produced and secreted by the testes. Androgen induced development causes the elongation and differentiation of the phallus into a penis, a fusion of the urogenital folds surrounding the urethral groove along the ventral surface of the penis, and a midline closure of the labioscrotal folds. This closure forms the wall of the scrotum the external genitalia. The external genitalia are completely formed by the end of the 12th week. [10] [11]

At birth, the development of the prepubertal male reproductive system is completed. During the second trimester of pregnancy, testosterone secretion in the male declines so that at birth the testes are inactive. [12] Gonadotropin secretion is low until the beginning of puberty. [13]

Summary Edit

The genetic sex is determined by whether a Y bearing or next bearing sperm fertilizes the open the presence or absence of a Y chromosome in turn determines whether the gonads of the embryo will be testes or ovaries and the presence or absence of testes, finally, determines whether the sex accessory organs and external genitalia will be male or female. This sequence is understandable in light of the fact that both male and female embryos develop within the maternal environment - high in estrogen secreted by the mother's ovaries and the placenta. If estrogen determined the gender, all embryos would become feminized. [10]

Puberty Edit

During puberty, increased gonadotropin secretion stimulates a rise in sex steroids creation from the testes. The increased secretion of testosterone from the testes during puberty causes the male secondary sexual characteristics to be manifested. [14]

Male secondary sex characteristics include:

  • Growth of body hair, including underarm, abdominal, chest hair and pubic hair. [15][16]
  • Growth of facial hair. [16]
  • Enlargement of larynx (Adam's apple) and deepening of voice. [16][17]
  • Increased stature adult males are taller than adult females, on average. [16]
  • Heavier skull and bonestructure. [16]
  • Increased muscle mass and strength. [16]
  • Broadening of shoulders and chest shoulders wider than hips. [18]
  • Increased secretions of oil and sweat glands. [17]

Secondary development includes the increased activity of the eccrine sweat glands and sebaceous glands along with the darkening of the skin in the scrotal region. [13]


How Does the Male Reproductive System Function?

The entire male reproductive system is dependent on hormones, which are chemicals that regulate the activity of many different types of cells or organs. The primary hormones involved in the male reproductive system are follicle-stimulating hormone, luteinizing hormone, and testosterone.

Follicle-stimulating hormone is necessary for sperm production (spermatogenesis), and luteinizing hormone stimulates the production of testosterone, which is also needed to make sperm. Testosterone is responsible for the development of male characteristics, including muscle mass and strength, fat distribution, bone mass, facial hair growth, voice change, and sex drive.


Ejaculation

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Ejaculation, the release of sperm cells and seminal plasma from the male reproductive system. Ejaculation takes place in two phases: in the first, or emission, stage, sperm are moved from the testes and the epididymis (where the sperm are stored) to the beginning of the urethra, a hollow tube running through the penis that transports either sperm or urine in the second stage, ejaculation proper, the semen is moved through the urethra and expelled from the body.

Sperm cells that are stored in the male body are not capable of self-movement because of the acidity of the accompanying fluids. When the sperm receive fluids, called seminal plasma, from the various internal accessory organs (prostate gland, ejaculatory ducts, seminal vesicles, and bulbourethral glands), the acidity decreases. As they leave the body, the sperm receive oxygen, which is vital to motility. Unable to leave the male body by their own motivation, the sperm cells are transported by muscular contractions. During the emission phase, the muscles around the epididymis and ductus deferens (the tube extending from the epididymis) contract to push the sperm into the prostate and urethra. During ejaculation, the semen is expelled by strong spasmodic contractions of the bulbocavernosus muscle, which encircles the corpus spongiosum (the structure in the penis that encloses the urethra). The whole process of ejaculation is accomplished by nerve impulses received from the penis once ejaculation is started it becomes a reflex reaction that cannot be voluntarily interrupted.

The seminal fluid is not passed from the various accessory glands simultaneously. A small amount of mucuslike secretion is first passed from the bulbourethral and urethral glands to flush out the urethra and prepare it for the sperm. Next follows the fluid from the prostate gland, and then that from the seminal vesicles. Finally, the fluid actually containing the sperm is ejaculated. After the bulk of the sperm cells have passed, more fluids follow and again flush out the urethra. The total volume of the ejaculate averages between 2 and 5 millilitres (0.12 to 0.31 cubic inch) in the human of this, only about 1 to 5 percent are actually sperm cells. The other constituents of semen include nutrients, water, salts, waste products of metabolism, and cellular debris. The secretions of the testes and accessory glands are produced under the influence of the male hormone testosterone without sufficient testosterone the glands degenerate and cannot secrete fluids. See also erection.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by John P. Rafferty, Editor.


Which process is needed to complete male reproductive development? - Biology

Select two correct functions of the male reproductive system from the list below.

  1. ? All males are born with one testicle.
  2. ? The testicles produce millions of sperm.
  3. ? Hormones are produced by the testicles.
  4. ? Semen is produced in the seminal vesicles.
  1. ? production of sperm best takes place at a temperature lower then body temperature.
  2. ? there is no room to fit the testicles inside the body.
  3. ? the sperm have a shorter distance to travel during intercourse.
  4. ? more sperm can be created.
Name the parts labelled A and B in the diagram
  1. ? A = scrotum, B = urethra
  2. ? A = prostrate gland, B = urethra
  3. ? A = scrotum, B = prostrate gland
  4. ? A = sperm duct, B = penis
Name the parts labelled A and B in the diagram
  1. ? A = penis, B = testicle
  2. ? A = penis, B = urethra
  3. ? A = scrotum, B = testicle
  4. ? A = testicle, B = penis
Name the part labelled X in the diagram that produces fluids which help the sperm to swim.
  1. ? 12 to 14 years of age
  2. ? 20 years of age
  3. ? 10 to 11 years of age
  4. ? 16 to 18years of age
Identify the parts labelled A and B in the diagram of a sperm shown
  1. ? A = head, B = tail
  2. ? A = nucleus, B = tail
  3. ? A = head, B = nucleus
  4. ? A = nucleus, B = leg
  1. ? His hair turns grey
  2. ? His voice deepens
  3. ? Hair grows on the chest and under the arms
  4. ? Sperm starts to be produced
  1. ? His shoulders broaden.
  2. ? The colour of his eyes change.
  3. ? He produces eggs.
  4. ? He stops playing with toys.
The diagram shows a sperm. The tail enables the sperm to swim. Why does the sperm need to be able to swim?
  1. ? In order to get to the egg.
  2. ? So that it does not drown in the semen.
  3. ? To travel around in the testicle.
  4. ? Because it is a member of the fish family.
During sexual intercourse, the erect penis is placed inside the vagina of the woman. Which one of the following statements is incorrect?

Male Reproductive System

The male reproductive system is a grouping of organs that make up a man’s reproductive and urinary systems. These organs do the following jobs within your body:

  • They produce, maintain and transport sperm (the male reproductive cells) and semen (the protective fluid around the sperm).
  • They discharge sperm into the female reproductive tract.
  • They produce and secrete male sex hormones.

The male reproductive system is made up of internal (inside your body) and external (outside your body) parts. Together, these organs help you urinate (rid your body of liquid waste materials), have sexual intercourse and make children.

What are the external male reproductive structures?

Most of the male reproductive system is located outside of your abdominal cavity or pelvis. The external parts of the male reproductive system include the penis, the scrotum and the testicles.

The penis is the male organ for sexual intercourse. It has three parts:

  • The root: This is the part of the penis that attaches to the wall of your abdomen.
  • The body or shaft: Shaped like a tube or cylinder, the body of the penis is made up of three internal chambers. Inside these chambers there’s a special, sponge-like erectile tissue that contains thousands of large spaces that fill with blood when you’re sexually aroused. As the penis fills with blood, it becomes rigid and erect, which allows for penetration during sex. The skin of the penis is loose and elastic, allowing for changes in penis size during an erection.
  • The glans: This is the cone-shaped end of the penis. The glans, which is also called the head of the penis, is covered with a loose layer of skin called foreskin. This skin is sometimes removed in a procedure called circumcision.

The opening of the urethra — the tube that transports both semen and urine out of the body — is located at the tip of the glans penis. The penis also contains many sensitive nerve endings.

Semen, which contains sperm, is expelled (ejaculated) through the end of the penis when a man reaches sexual climax (orgasm). When the penis is erect, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.

The scrotum is the loose pouch-like sac of skin that hangs behind the penis. It holds the testicles (also called testes), as well as many nerves and blood vessels. The scrotum protects your testes, as well as providing a sort of climate control system. For normal sperm development, the testes must be at a temperature slightly cooler than the body temperature. Special muscles in the wall of the scrotum allow it to contract (tighten) and relax, moving the testicles closer to the body for warmth and protection or farther away from the body to cool the temperature.

Testicles (testes)

The testes are oval organs about the size of very large olives that lie in the scrotum, secured at either end by a structure called the spermatic cord. Most men have two testes. The testes are responsible for making testosterone, the primary male sex hormone, and for producing sperm. Within the testes are coiled masses of tubes called seminiferous tubules. These tubules are responsible for producing the sperm cells through a process called spermatogenesis.

The epididymis is a long, coiled tube that rests on the backside of each testicle. It carries and stores sperm cells that are created in the testes. It’s also the job of the epididymis to bring the sperm to maturity — the sperm that emerge from the testes are immature and incapable of fertilization. During sexual arousal, contractions force the sperm into the vas deferens.

What are the internal male reproductive organs?

You have several internal organs — also called accessory organs — that play a big part in the male reproductive system. These organs include:

  • Vas deferens: The vas deferens is a long, muscular tube that travels from the epididymis into the pelvic cavity, to just behind the bladder. The vas deferens transports mature sperm to the urethra in preparation for ejaculation.
  • Ejaculatory ducts: These ducts are formed by the fusion of the vas deferens and the seminal vesicles. The ejaculatory ducts empty into the urethra.
  • Urethra: The urethra is the tube that carries urine from the bladder to outside of your body. In males, it has the additional function of expelling (ejaculating) semen when you reach orgasm. When the penis is erect during sex, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.
  • Seminal vesicles: The seminal vesicles are sac-like pouches that attach to the vas deferens near the base of the bladder. The seminal vesicles make a sugar-rich fluid (fructose) that provides sperm with a source of energy and helps with the sperms’ ability to move (motility). The fluid of the seminal vesicles makes up most of the volume of your ejaculatory fluid, or ejaculate.
  • Prostate gland: The prostate gland is a walnut-sized structure that’s located below the urinary bladder in front of the rectum. The prostate gland contributes additional fluid to the ejaculate. Prostate fluids also help to nourish the sperm. The urethra, which carries the ejaculate to be expelled during orgasm, runs through the center of the prostate gland.
  • Bulbourethral glands: The bulbourethral glands, or Cowper’s glands, are pea-sized structures located on the sides of the urethra, just below the prostate gland. These glands produce a clear, slippery fluid that empties directly into the urethra. This fluid serves to lubricate the urethra and to neutralize any acidity that may be present due to residual drops of urine in the urethra.

How does the male reproductive system function?

The entire male reproductive system is dependent on hormones. These are chemicals that stimulate or regulate the activity of your cells or organs. The primary hormones involved in the functioning of the male reproductive system are follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone.

FSH and LH are produced by the pituitary gland. It’s located at the base of the brain and it’s responsible for many functions in your body. FSH is necessary for sperm production (spermatogenesis). LH stimulates the production of testosterone, which is necessary to continue the process of spermatogenesis. Testosterone is also important in the development of male characteristics, including muscle mass and strength, fat distribution, bone mass and sex drive.

Can a man go through menopause?

Menopause is a term used to describe the end of a woman's normal menstrual function. In women, this is marked by changes in hormone production. One of the biggest changes for a woman after menopause is that she can no longer have children. The testes, unlike the ovaries, do not lose the ability to make hormones. If a man is healthy, he may be able to make sperm well into his 80s or longer.

On the other hand, subtle changes in the function of the testes can happen as early as 45 to 50 years of age, and more dramatically after the age of 70. For many men, hormone production may remain normal into old age, while others may have declining hormone production earlier on. This can sometimes be a result of an illness, such as diabetes.

It’s unclear whether decreasing testicular function contributes to symptoms like fatigue, weakness, depression or impotence.

Can "male menopause" be treated?

If your testosterone levels are low, hormone replacement therapy may help relieve symptoms, such as the loss of interest in sex, depression and fatigue. However, replacing male hormones can make prostate cancer worse, and may make atherosclerosis (hardening of the arteries) worse, also.

You should receive a complete physical examination and laboratory tests should be performed before starting hormone replacement therapy. There are still many unanswered questions about how many middle-aged men could benefit from hormone replacement therapy. Talk to your healthcare provider about all the pros and cons of this treatment and what the best option is for you.


Male reproductive system disease

Male reproductive system diseases are Hypospadias, hydrocele, Varicocele, Cryptorchidism, Benign prostatic hypertrophy (BPH) , Transurethral resection of the prostate (TURP), Prostate Specific Antigen (PSA), eunuchoidism and Gynaecosmastia

Hypospadias:- it mean literally “below the fleshy spike.” hypospadias is characterized by a condition in which the external urinary meatus that is top opening opens anywhere below the tip of the penis rather than at the tip.

Hydrocele – it is more common human male reproductive system disease which is characterized by a fluid filled sac partially surrounding the testis. Manifests itself as a swelling on the side of the scrotum wall. It may cause discomfort. Can be surgically corrected by the doctor. Urologist are expert in their surgery of hydrocele.

Varicocele – dilated and twisted veins of the testis, look like sort of “hemorrhoids” in the scrotum, it manifests itself as a swelling on the side of the scrotum wall which may look and feel like a “bag of worms.” it may be surgically corrected by Urologist doctor if causing discomfort. This condition varicocele may also cause reduced sperm count in male and male sterility due to sluggish blood flow elevating testicular temperature.

Cryptorchidism – it literally known as “hidden testicle.” A condition of lack of descent of one or both testes into the scrotum wall or scrotal sac. If it is not corrected early by Urologist doctor by surgery, before puberty, can lead to sterility and increased risk of testicular cancer.

Benign prostatic hypertrophy (BPH) – it is characterized by swelling of the prostate gland which surrounds the base of the male bladder and urethra causing difficulty in urinating, dribbling, and nocturia. BPH becomes more common as men age.

Transurethral resection of the prostate (TURP) – it is characterized by the surgical removal and cure for BPH. An instrument inserted through the penile urethra is used to partially cut away the prostate to relieve obstruction of the urinary tract.

Prostate Specific Antigen (PSA) – it is characterized by, it is a marker protein for prostate cell secretions which can be detected with a lab test in laboratory. A rising PSA may be an early sign of prostate cancer, although there may be other causes including false positive tests.

Eunuchoidism:- failure of testosterone secretion causes eunuchoidism. It is characterized by underdeveloped and nonfunctional secondary sex organs, lack of accessory sex character and does not produce sperm. Administration of testosterone to eunuch stimulate development of accessory sex character and secondary sex organ.

Gynaecosmastia:- excessive development of mammary gland in male is term Gynaecosmastia. it is developed in male when oestrogen secretion is more than those of androgens. it may occur in newly born and at the property due to temporary increase in circulating estrogens. Gynaecosmastia may also occur in later life due to deficiency of testosterone hormone.


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