SEXUAL ORGANS DEEPENING
I’m sure most people, and young especially, are not very familiar with our organs and their functioning. Our body is a masterpiece difficult to conceive, just think of our brain and mind to realize this. But beyond complex or internal organs on which you do not need in-depth knowledge, we all should know a little about sexual organs, our reproductive organs we see and use every day. Not being gynecologists or urologists, there is no need to go into detail, and beyond some scientific detail or strange name, we should understand how these organs work, to be then able to understand their possible dysfunction.
I will examine both male and female sexual organs, simply telling the most important things, and I hope that for you who follow me the reading will be fluent and interesting. As well as I hope that the images, necessary in these cases, do not disturb anyone, convinced that in 2013 no one should feel embarrassed or troubled anymore by such images. [Click on any image to magnify it].
In most “civilized” human societies, genitals are considered a public indecency and sometimes even illegal if left uncovered in public. It ranges from prohibition of exposure of genital areas, buttocks and female breasts. In some Islamic countries the exposure of any part of the female body is even considered indecent. If sexual acts are performed, with or without an element of nudity, this can be considered a public indecency, which may be a more serious criminal offense. Presently, public nudity isn’t permitted in any country and in some states it is only allowed on specific sites that have been assigned by the local authorities. I realize that the post is long because too many things to say, but you can read it a little at a time, if you really are determined to learn more.
As always, I remain at your disposal for any question or friendly comment.
EXTERNAL PARTS: VULVA
The term “VULVA” refers to the external part of the VAGINA that has major and minor anatomical structures including:
opening of the vagina
Let’s take a look at each of these parts now.
also known as “mons veneris” or “mound of Venus”, is the adipose tissue lying above the pubic bone (pelvis), the area where during puberty hair start to grow. Its size is depending by genetic factors and body fat. It’s an erogenous zone because from it take form the “larger lips”, the most external organ of the vagina called labia major.
(nicknamed camel toe), is part of vulva like two long lips that have the purpose to protect the vagina, in fact around them we also find hair. They extend from the mound till perineum, where some centimeters after come the anus. Depending on personal characteristic, the labia major can be more or less open and with different shape, size and color. A 2004 research says that average length ranges within 7.0 – 12.0 cm. A little bit inside from these lips, to either side of the opening of the vagina, develop other two smaller lips, the labia minora.
or inner labia, are another protection for the vagina opening. These inner two flaps of skin also change in size and shape from woman to woman and, either can be absent or fleshy/long till to appear outside labia major. A 2004 research says that average length ranges from 2 -10 cm. The inner skin of these labia forms a small cavity called vestibule. In the upper part of the vestibule is the clitoral hood, followed by the female urethral orifice, while almost in middle is the vulval vestibule with the vaginal opening (vagina), the orifice used for sexual penetration (although these holes are very close with one another, the urethral orifice is too small for man to get a wrong target!) Mons together labia major and minor are the main responsible of the external shape of the pussy.
is the human female’s most sensitive erogenous zone and the primary source of female sexual pleasure. Clitoris and penis have generally the same anatomical structure, although the opening of the urethra is absent in the clitoris of humans and therefore not used for urination. In fact, during the fetal development the clitoris forms from the same tissues that become the penis in male. The visible button-like portion, called glans (head), near the front junction of the inner lips, above the opening of the urethra, is what people generally refers when talking about clitoris. The glans of the clit is roughly the size and shape of a pea, and has more sensory nerve endings than any other part of the female body, and for this it’s the key to female sexuality. A 2004 research says that its length ranges from 0.5 –3.5 cm. Instead, the whole clitoris is a complex structure, containing external and internal components: glans, the frenulum clitoridis (a frenulum on the under-surface of the glans), the clitoral body or shaft (with the shaft being external and internal), the clitoral hood, two erectile bodies known as the corpora cavernosa, two clitoral crura and the vestibular or clitoral bulbs. Although the glans is usually small, it can assume different shapes and sizes, with some woman in which it even appears as a small penis (clitoromegaly).
The clitoral body/internal shaft forms a wishbone-shaped structure containing the corpora cavernosa – a pair of sponge-like regions of erectile tissue which contain most of the blood in the clitoris during clitoral erection that usually happens during sexual arousal. The clitoris is rich in its capacity to receive sexual stimulation, which may be explored with a sexual partner or by masturbation. The sexual arousal coming through the clitoral stimulation brings the vaginal duct to lubricate and enlarge itself, predisposing it for a possible penis penetration. The most effective sexual stimulation of this organ is usually through direct stimulation by manual (fingering) or oral stimulation, although these areas may receive indirect physical stimulation during sexual activity (penile penetration), when man’s pubis rubbings and pushes also brings the clit to be stimulated someway. Penile-anal penetration may also indirectly stimulate the clitoris, either by the shared sensory nerves (especially the pudendal nerve or by the crura extending beneath and along the labia minora back to the anus). Anyway, the direct stimulation gives back the highest pleasure, also if due to the glans’s high sensitivity, for a few women the direct stimulation becomes sometimes unfeasible. Usually, fingers that have been lubricated, either by vaginal lubrication or a personal lubricant, is more pleasurable for the external anatomy of the clitoris. During sexual arousal, the vaginal contractions and the persistent vasocongestion eventually “set off a muscular reflex” which expels the blood that was trapped in surrounding tissues, and lead to an orgasm. And after orgasm, unlike men, the clitoris even becomes more sensitive. The majority of women, 70 percent for general statistics, require direct clitoral stimulation to achieve a faster orgasm. The area near the entrance of the vagina (the lower third) contains nearly 90 percent of the vaginal nerve endings, and there are areas in the anterior vaginal wall and between the top junction of the labia minora and the urethra that are especially sensitive, but intense sexual pleasure and orgasm from vaginal stimulation is occasional because the vagina has significantly fewer nerve endings than the clitoris.
Opening of the vagina
is the last visible part of the vulva, also if to see it often needs to keep open the labia. With it anatomically the vulva ends, and the vagina begins, i.e. the female sexual organs for reproductive purpose. This orifice is below and behind the opening of the urethra and its size varies inversely with that of the hymen. Undoubtedly, this orifice is the narrowest part of the vagina that wider as it goes in deeper through an average diameter that is less than one inch. Size changes when ready for intercourse and according to its size and elasticity, for some girls even inserting a tampon can be difficult, resulting a painful penile-penetration.
INTERNAL PARTS: VAGINA
The female internal sexual and reproductive organs are:
Let’s take a look at each of these parts now.
Vagina has insufficient nerve endings for sexual stimulation and orgasm, which is considered to make the process of child birth significantly less painful. The outer one-third of the vagina, especially near the opening, contains the majority of the vaginal nerve endings, making it more sensitive Orgasm also known as sexual climax, is the sudden discharge of accumulated sexual tension during the sexual response cycle, resulting in rhythmic muscular contractions in the pelvic region characterized by an intense sensation of pleasure. Discussions of female orgasm are complicated by orgasms in women typically being divided into two categories: clitoral orgasm Apart from the difficulty reaching orgasm after ample sexual stimulation (anorgasmia), significantly more common in women than in men, the amount of time for sexual arousal needed to reach orgasm is more variable and longer in women than in men. Masters and Johnson found that men took about 4 minutes to reach orgasm with their partners. Women took about 10–20 minutes to reach orgasm with their partners, but 4 minutes to reach Finally, the vagina also provides a path for menstrual blood and tissue to leave the body.
Is a membranethat surrounds or partially covers the external vaginal opening. In children, at month 5 the vaginal canalization is complete and the fetal hymen is already formed although a common appearance of the hymen is crescent-shaped, many shapes are possible. At this age, the hymen is thick, pale pink, and redundant (folds in on itself and may protrude). By the time a girl reaches school age, the hymen becomes thin, smooth, delicate, and nearly translucent, and can also become very sensitive to touch. Once a girl reaches puberty, the hymen tends to become very elastic. The effects of sexual intercourse and childbirth on the hymen are variable. If the hymen is sufficiently elastic, it may return to nearly its original condition. In other cases, there may be remnants, or it may appear completely absent after a penetration. The hymen may be lacerated by disease, injury, medical examination, masturbation or even physical exercise. For these reasons, it is not possible to definitively determine whether or not a girl or woman is a virgin (meaning no penile-penetration) by examining her hymen, given that an intact hymen is socially highly valued to show virginity. Although the hymen is usually flexible and can be torn during first engagement in vaginal intercourse, women can possess a thin very fragile hymens or a thick very tough one. In the first case, its laceration can lead no bleeding and without the girl even being aware of it. On the contrary, in some cases the break of the hymen is cause of abundant bleeding that can last long. In one survey, only 43% of women reported bleeding the first time they had intercourse.
or the neck of the uterus, is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall like an funnel, representing the end of the vaginal duct. Therefore, any long object or penis inserted, longer than vaginal’s duct, it will inexorably hit the cervix. The cervix has a very small opening to allow sperm or menstrual fluid to move through.
or womb, is a major female responsive reproductive sex organ. It is a pear-shaped muscular organ with the main function to accept a fertilized ovum (egg) which becomes implanted into the endometrium, then becoming later an embryo. In this case, the uterus provides for nourishment from blood vessels which develop exclusively for this purpose. In the absence of fertilization (by a spermatozoa), the egg does not embed in the wall of the uterus, and a female begins menstruation. If the ovum has been fertilize in the Fallopian tubes, it then becomes an embryo, attaches to a wall of the uterus, creates a placenta, and develops into a fetus (gestates) until childbirth. Due to anatomical barriers such as the pelvis, the uterus is pushed partially into the abdomen due to its expansion during pregnancy.
also known as oviducts, are two very fine tubes leading from the ovaries into the uterus that allows passage of the egg from the ovary to the uterus. On maturity of the ovum, the follicle and the ovary’s wall rupture, allowing the ovum to escape. The egg is caught by the fimbriated (fringelike) end and travels to the ampulla, where typically the sperm are met and fertilization occurs. This second portion of the uterine tube is puffed-up and sunken to let sperms to be collected.The fertilized ovum, now a zygote, travels towards the uterus aided by activity of tubal cilia and activity of the tubal muscle. After about five days the new embryo enters the uterine cavity and implants about a day later.
are two reproductive organs producing eggs (ovum) through a process called ovulation. For this reason, ovary can be considered analogous to testes in male individuals. The ovary (for a given side) is about the size and shape of an almond and located in the lateral wall of the pelvis which it is connected. Every month during ovulation, either the right or left ovary produces a single mature egg for fertilization. The ovum is one of the largest cells in the human body measuring approximately 0.12 mm in diameter. The few days near ovulation constitute the fertile phase for women. After ovulation, the egg only lives
for 24 hours or less without fertilization. If no conception occurs, the uterine lining as well as egg and blood will be shed in menstruation (during menstrual cycle or period). In industrial societies, tampons, menstrual cups and sanitary napkins may be used to absorb or capture these fluids. Menstruation starts (with menarche) at or before sexual maturity (puberty) and ceases at or near menopause (commonly considered the end of a female’s reproductive life when ovary’s follicles stop producing ovum).
Let’s take a look at each of these parts now.
similar to female mons pubis, is located on and around the sex organs (crotch) which in male, though has no intrinsic sexual value, is considered an erotic zone, especially if covered with hair. In fact, it’s one of the most hairy male’s body part that start during puberty (pubarche). Aside from the head, scientists’ common explanation on such a large development of hair (long and sparse) in this area, is to control the temperature which, especially for the testicles, should be less than that of the body.
is a reproductive organ that additionally serves as the urinal duct. It’s a intricate organ whose external part are:
shaft (body or corpus)
foreskin and shaft skin (epithelium)
urethra orifice (meatus)
The body is a fleshy appendix without internal bone, whose most part is inside the pubic region, and covered with cutaneous skin which from abdomen then differentiates along in foreskin and glans’s skin. It is devoid of hair having no hair follicles. On the ventral underside of the shaft is visible a line or ridge of tissue that extends from the anus, through th e scrotum and till foreskin which is called perineal raphe.
On entering puberty, the penis, scrotum and testicles will begin to develop. During the process, pubic hair grows above and around the penis. A large-scale study assessing penis size in thousands of 16–18 year old males found no difference in average penis size between 17 year olds and 19 year olds. From this, it can be concluded that penile growth is typically complete not later than age 17, and possibly earlier.
The variability in size due to arousal level, time of day, temperature, frequency of sexual activity, and reliability of measurement, gives back a difficult measurement of the penis and thus we only can talk about average sizes. Besides, the size of the penis when in “normal” (flaccid, relaxed or non-tumescent) state is still more variable since the penis and scrotum can contract involuntarily in reaction to cold temperatures or nervousness. Anyway, a review of several studies found average flaccid length to be 8–10 cm (3.2–3.9 in) and a diameter of 3.2 cm (1.25 inches). Researchers conclude that flaccid penile length is just under 4 cm (1.6 in) at birth and changes very little until puberty when there is marked growth, apart a limited growth between birth and 5 years of age. It has been suggested that differences in penis size between individuals are caused mostly by genetics, though also environmental factors such as culture, diet, chemical/pollution exposure, can affect the size. The internal morphology of the penis is made to produce erections, namely to bring the penis to increase in size and become a straight stiff appendix, for reproductive reasons.
Thus, an erection is the stiffening and rising of the penis, and this occurs during sexual arousal, though it can also happen in non-sexual situations. The primary physiological mechanism that brings about erection is the autonomic dilation of arteries supplying blood to the penis, which allows more blood to fill the three spongy erectile tissue chambers in the penis, causing it to lengthen and stiffen. The now-engorged erectile tissue presses against and constricts the veins that carry blood away from the penis. More blood enters than leaves the penis until an equilibrium is reached where an equal volume of blood flows into the dilated arteries and out of the constricted veins; so, a constant erectile size is achieved at this equilibrium. While results vary slightly across different studies, the consensus is that the average of fully erect penis ranges within 12,9 – 16 cm (5.1– 6.3 in) in length. Similar results exist regarding studies of the circumference of the adult fully erect penis, with the measurement taken mid-shaft. In three studies of penis size where measurements were taken in a laboratory setting, the range of average penis circumference when erect was 3.5 to 3.9 inches (8.9 to 9.9 centimetres).
When in erect state, the shaft usually tends to be thicker at the base becoming more thinned until the beginning of the “head”, a formation conical-shaped called the glans penis. Although many erect penises point straightly upwards, it is common and normal for the erect penis to point a little bit nearly vertically upwards or nearly vertically downwards or even horizontally straight forward, all depending on the tension of the suspensory ligament that holds it in position. Anyhow, a curvature not bigger than 30° still can be considered normal. As the vulva, the erect penis may appear in different shapes, varying in diameter, length, bend, shape of the glans and body, where aside from size, is its body shape and the glans size to affect more.
The skin covering the penis, very soft and supple, around the glans buy a different structure called foreskin or prepuce. As the most part of the shaft, the foreskin also is devoid of hair. It is a double-layered fold of skin and mucous membrane whose main purpose is to cover and protect the glans and the urinary meatus, when the penis is not erect, but it is also an element co-operating during intercourse (penile-penetration), whose gliding movements (stretched-wrapped) helps arousal, adding comfort and pleasure of both parties. In fact, foreskin is rich in specialized sensory nerve endings and erogenous tissue. The foreskin is (or should be) retractable over the glans. Like the eyelid, it is free to move after it separates from the glans, usually after birth or before puberty. Smooth muscle fibres keep it close to the glans but make it highly elastic. The foreskin is attached to the glans by a frenulum, which helps return the foreskin over the glans. This frenulum should be the right length to let prepuce go back and forth in an easy way. Many researchers believe that the presence of the foreskin made sexual penetration easier as an erogenous tissue necessary for normal sexual function. Well documented is the complex innervation of the foreskin and frenulum, as the genitally intact male has thousands of fine touch receptors (Meissner’s corpuscles) and other highly erogenous nerve endings giving back a sensory mucosa.
The preputial mucosa of the penis is the epithelium of the inside of the prepuce, or foreskin. To differentiate it from the cutaneous skin of the outside of the prepuce, it is sometimes referred to as the inner mucosa. It starts at the ridged band of the prepuce and continues to the coronal sulcus (groove behind the glans penis), where it meets the epithelium of the glans and penile shaft. In circumcised infants, the foreskin no longer protects the meatal area of the glans; consequently, when wearing diapers, there may be greater risk of developing meatitis, meatal ulceration, and meatal stenosis. Finally, we must also consider that every part of our body, after thousands of years of evolution, has not been put there without a purpose and that it may not be unnecessary or superfluous. Foreskin length can vary from man to man with cases in which it is so short to hardly cover the glans or so abundant to fully cover the glans even during the erection.
is the sensitive bulbous structure at the distal end of the human penis. The glans penis is anatomically homologous to the clitoral glans of the female. The glans is also commonly referred to as the “head” of the penis, while common British slang terms include “helmet,” “knob end,” “popper” and “bell end”, all referring to its distinctive shape. It is generally completely or partially covered by the foreskin, except in men who have been fully circumcised. The circumference of the base of the glans forms a rounded projecting border, the corona glandis, overhanging a deep retro-glandular sulcus (the coronal sulcus), behind which is the neck of the penis. The proportional size of the glans penis can vary greatly. On some penises it is much wider in circumference than the shaft, giving the penis a mushroom-like appearance, and on others it is narrower and more akin to a probe in shape. The glans is the most sensory structure of the penis, containing a predominance of free nerve endings and numerous genital end bulbs. It has been suggested that the unique and unusual shape of the glans in humans has evolved to serve the function of “scooping” any remnant semen deposited by other rival males out of the deeper part of the vagina of a female who may have recently copulated, and thereby decreasing the chance of the rival male from impregnating the female. Other theorists suggest that its distinctive shape evolved to heighten the sexual pleasure experienced by the female during vaginal intercourse. In this theory, the glans increases friction and tension at the mouth of the vagina by its additional girth and the dilating properties of its probe-like shape.
At the summit of the glans is the slit-like vertical external urethral orifice.
In males, the expulsion of urine from the body is done through the male penis. The urethra drains the bladder through the prostate gland where it is joined by the ejaculatory duct, and then onward to the penis. At the root of the penis (the proximal end of the corpus spongiosum) lies the external sphincter muscle. Relaxing the urethra sphincter allows the urine in the upper urethra to enter the penis proper and thus empty the urinary bladder. The part of the urethra in the penis has no muscles, and this serves no physiological function beyond that of a duct. Small amounts of urine usually remaining in the distal portion of the urethra, seeping out after the voluntary expulsion of urine is over.
the scrotum is a dual-chambered protuberance of skin and muscle, containing the testicles (numerous nerves and blood vessels) and divided by a septum. The scrotum is homologous to the labia majora in females. It looks like a sack hanging behind the penis and between the legs, both sides with two oval balls inside and that becomes covered with pubic hairs at puberty. The function of the scrotum appears to be to keep the temperature of the testes slightly lower than that of the rest of the body. For human beings, the scrotum temperature should be about 35-36 degrees Celsius (95-96.8 degrees Fahrenheit) , i.e. one to two degrees Celsius below the accepted normal body temperature of 37 degrees Celsius (98.6 degrees Fahrenheit). Higher temperatures may be damaging to sperm count. According to other authors, the testicles are not directly attached to the skin of the scrotum or inside, to keep them outside the abdominal cavity where they would be subjected to the regular changes in abdominal pressure. While an alternative explanation is to protect the testes from jolts and compressions associated with an active lifestyle. 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 relaxes 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, where at birth (or later before puberty) the testes go cross to reach the sack.
INTERNAL PARTS OF THE PENIS.
The human penis is made up of three columns of tissue: two corpora cavernosa lie next to each other on the dorsal side and one corpus spongiosum lies between them on the ventral side, and the urethra.
The corpus cavernosum penis is one of a pair of sponge-like regions of erectile tissue which contain most of the blood in the penis during penile erection. Erectile tissue is tissue in the body with numerous vascular spaces that may become engorged with blood.
Corpus spongiosum is the mass of spongy tissue surrounding the male urethra in a smaller region along the bottom of the penis. The enlarged and bulbous-shaped end of the corpus spongiosum forms the glans penis, which supports the foreskin. The function of the corpus spongiosum in erection is to prevent the urethra from pinching closed, thereby maintaining the urethra as a viable channel for ejaculation. To do this, the corpus spongiosum remains pliable during erection while the corpora cavernosum penis becomes engorged with blood.
The urethra, which is the last part of the urinary tract, traverses the corpus spongiosum, and its opening, known as the meatus, lies on the tip of the glans penis. It is a passage both for urine and for the ejaculation of semen. During ejaculation, sperm are propelled up the vas deferens, two ducts that pass over and behind the bladder. Fluids are added by the seminal vesicles and the vas deferens turns into the ejaculatory ducts, which join the urethra inside the prostate gland, and the semen is expelled through the penis. The distal section of the urethra (thanks to penis) does however allow a human male to direct the stream of urine by holding the penis. In cultures where more than a minimum of clothing is worn, the penis allows the male to urinate while standing and orientate the flow.
INTERNAL PART OF SCROTUM
is part of the male reproductive system and is a single, narrow, tightly-coiled tube (in adult humans, six to seven meters in length) connecting the efferent ducts from the rear of each testicle to its vas deferens. The epididymis is a whitish mass of tightly coiled tubes cupped against the testicles. It acts as a maturation and storage place for sperm before they pass into the vas deferens, tubes that carry sperm to the ampullary gland and prostatic ducts. Spermatozoa formed in the testis enter the head of epididymis, progress to the corpus, and finally reach the lower region (tail), where they are stored. Sperm entering the epididymis are incomplete – they lack the ability to swim forward (motility) and to fertilize an egg. It stores the sperm for 2–3 months. During their transit in the epididymis, sperm undergo maturation processes necessary for them to acquire these functions.
also known as the sperm duct, is a thin tube approximately 43 centimetres long that starts from the epididymis to the pelvic cavity and transport sperm from the epididymis in anticipation of ejaculation. There are two ducts, connecting the left and right epididymis to the ejaculatory ducts in order to move sperm. Each tube is about 30 centimeters long and is muscular, surrounded by smooth muscle that during ejaculation contracts reflexively propelling the sperm forward. The sperm is transferred from the vas deferens into the urethra, collecting secretions from the male accessory sex glands such as the seminal vesicles, prostate gland and the bulbourethral glands, which form the bulk of semen.
are the seminal vesicles, prostate gland, and the bulbourethral glands (Cowper glands).
Three accessory glands provide fluids that lubricate the duct system and nourish the sperm cells.
or vesicular glands are a pair of simple tubular glands posteroinferior to the urinary bladder located within the pelvis. Seminal vesicles are sac-like structures attached to the vas deferens at one side of the bladder. They produce a sticky, yellowish fluid that contains fructose. This fluid provides sperm cells energy and aids in their motility. 70% of the semen is its secretion.
The function of the prostate is to secrete a slightly alkaline fluid, milky or white in appearance, that usually constitutes 50–75% of the volume of the semen along with spermatozoa and seminal vesicle fluid. The alkalinity of semen helps neutralize the acidity of the vaginal tract, prolonging the lifespan of sperm. The prostate gland surrounds the ejaculatory ducts at the base of the urethra, just below the bladder and is responsible for the production of semen, a liquid mixture of sperm cells, prostate fluid and seminal fluid. This gland is also responsible for making the semen milky in appearance by mixing calcium to the semen coming from seminal vesicle (semen coming from the seminal vesicle is transparent in color).
The bulbourethral glands, also called Cowper glands, are two small exocrine glands present located on the sides of the urethra just below the prostate gland. These glands produce a clear, slippery fluid that empties directly the urethra. During sexual arousal each gland produces a clear, salty, viscous secretion known as pre-ejaculate (pre-cum). This fluid helps to lubricate the urethra for spermatozoa to pass through, neutralizing traces of acidic urine in the urethra.
Testiscle or testis
The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The primary functions of the testes are to produce sperm (spermatogenesis) and to produce androgens, primarily testosterone. It is most common for one testicle to hang lower than the other. While the size of the testicle varies, it is estimated that 21.9% of men have their higher testicle on left side, due to differences in the vascular anatomical structure on the right and left sides. The average testicle size after puberty measures up to around 2 inches long, 0.8 inches in breadth, and 1.2 inches in height (5 x 2 x 3 cm). Each testicle contains very fine coiled tubes called seminiferous tubules. The tubules are lined with a layer of cells (germ cells) that from puberty into old age, develop into sperm cells (also known as spermatozoa or male gametes). The developing sperm travel through the seminiferous tubules to the rete testis to the efferent ducts, and then to the epididymis where newly created sperm cells mature (spermatogenesis). The sperm move into the vas deferens, and are eventually expelled through the urethra and out of the urethral orifice through muscular contractions, called ejaculation (cum).
The term sperm (meaning “seed”) refers to the male reproductive cells. A uniflagellar sperm cell that is motile is referred to as a spermatozoon, whereas a non-motile sperm cell is referred to as a spermatium. The initial spermatozoon process takes around 70 days to complete. The spermatid stage is where the sperm develops the familiar tail. The next stage where it becomes fully mature takes around 60 days when it’s called a spermatozoan. Sperm cells are carried out of the male body in a fluid known as semen. Sperm cells consists of a head 5 µm (micrometer) by 3 µm and a tail 50 µm long (1 micrometer is 1×10−6 of a metre, about 0.000039 inches). Human sperm cells can survive within the female reproductive tract for more than 5 days post coitus. Sperm quantity and quality are the main parameters in semen quality, which is a measure of the ability of semen to accomplish fertilization. Thus, in humans, it is a measure of fertility in a man. A semen analysis typically measures the number of sperm per milliliter of ejaculate, and analyzes the morphology (shape) and motility (ability to swim forward) of the sperm (the typical ejaculate of a healthy, physically mature young adult male of reproductive age with no fertility-related problems usually contains 300-500 million spermatozoa. The genetic quality of sperm, as well as its volume and motility, all typically decrease with age. The human sperm cell is haploid, so that its 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell (zygote), and transmit our genetic characteristics. In mammals, the sex of the offspring is determined by the male sperm cell: a spermatozoon bearing a Y chromosome will lead to a male (XY) offspring, while one bearing an X chromosome will lead to a female (XX) offspring—the X chromosome. Unlike women, male gonad never stop to produce sperm, though decreasing with age. The force and amount of semen that will be ejected during an ejaculation will vary widely between men and may contain between 0.1 and 10 milliliters, though volume is affected by the time that has passed since the previous ejaculation.
The first ejaculation in males often occurs about 12 months after the onset of puberty, generally through masturbation or nocturnal emission (wet dreams). The typical ejaculation over the following three months produces less than 1 ml of semen. The semen produced during early puberty is also typically clear. After ejaculation this early semen remains jellylike and, unlike semen from mature males, fails to liquify. [The liquefaction is the process when the gel formed by proteins from the seminal vesicles is broken up and the semen becomes more liquid. It normally takes less than 20 minutes for the sample to change from a thick gel into a liquid. A liquefaction time within 60 minutes is regarded as within normal ranges]. Most first ejaculations (90 percent) lack sperm. Of the few early ejaculations that do contain sperm, the majority of sperm (97%) lack motion. The remaining sperm (3%) have abnormal motion. As the male proceeds through puberty, the semen develops mature characteristics with increasing quantities of normal sperm. Semen produced 12 to 14 months after the first ejaculation liquifies after a short period of time. Within 24 months of the first ejaculation, the semen volume and the quantity and characteristics of the sperm match that of adult male semen.
References: most of the content is from wikipedia.org