Chapter V - Male Reproduction
The bulbourethral glands (or Cowper's glands) are two small, rounded, and somewhat lobulated bodies, of a yellow color, about the size of peas, placed behind and lateral to the membranous portion of the urethra, between the two layers of the fascia of the urogenital diaphragm. They lie close above the bulb, and are enclosed by the transverse fibers of the Sphincter urethrae membranaceae. Their existence is said to be constant: they gradually diminish in size as age advances.
The excretory duct of each gland, nearly 2.5 cm long, passes obliquely forward beneath the mucous membrane, and opens by a minute orifice on the floor of the cavernous portion of the urethra about 2.5 cm in front of the urogenital diaphragm.
They secrete a clear fluid known as pre-ejaculate or Cowper's fluid (colloquially known as "pre-cum") which is generated upon sexual arousal.
Cowper's glands in males are homologous to Bartholin's glands in females.
The ejaculatory ducts are part of the human male anatomy, which cause the reflex action of ejaculation. Each male has two of them. They begin at the vas deferens, pass through the prostate, and empty into the urethra at the Colliculus seminalis. During ejaculation, semen passes through the ducts and exits the body via the penis.
The epididymis is part of the human male reproductive system and is present in all male mammals. It is a narrow, tightly-coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferens. The epididymis can be divided into three main regions, the head (caput), body (corpus) and tail (cauda). Sperm formed in the testis enter the caput epididymis, progress to the corpus, and finally reach the cauda region, where they are stored. Sperm entering the caput epididymis are incomplete - they lack the ability to swim forward (motility) and to fertilize an egg. During their transit in the epididymis, sperm undergo maturation processes necessary for them to acquire these functions. Sperm maturation is completed in the female reproductive tract (capacitation).
During ejaculation, sperm flow from the lower portion of the epididymis (which functions as a storage reservoir). They are packed so tightly that they are unable to swim, but are transported via the peristaltic action of muscle layers within the vas deferens, and are mixed with the diluting fluids of the seminal vesicles and other accessory glands prior to ejaculation (forming semen).
Inflammation of the epididymis is called epididymitis.
The foreskin or prepuce is a retractable double-layered fold of skin and mucous membrane that covers the glans penis and protects the urinary meatus when the penis is not erect. In humans, the outside of the foreskin is like the skin on the shaft of the penis but the inner foreskin is a mucous membrane like the inside of the eyelid or the mouth. This undersurface of the foreskin contains ectopic glands to produce emollients commonly called smegma, which some believe carry antibacterial proteins, although this can also lead to balanitis among persons with poor hygiene. In children, the foreskin covers the glans completely but in adults this need not be so.
Frenulum breve is where the frenulum is insufficiently long to allow the foreskin to fully retract, which may lead to discomfort during intercourse. The frenulum may also tear during intercourse.
Phimosis is a condition when the foreskin of an adult cannot be retracted properly. (Before adulthood, the foreskin may still be separating from the glans .) Phimosis can be treated by gently stretching the foreskin, using topical steroid ointments, preputioplasty, or by circumcision. See phimosis for more information.
A condition called paraphimosis may occur if a tight foreskin becomes trapped behind the glans and swells as a restrictive ring. This can cut off the blood supply ischaemia to the glans penis.
Aposthia is a rare condition in which the foreskin is not present at birth.
Surgical and other modifications of the foreskin
Circumcision is the removal of the foreskin, either partially or completely. It may be done for religious, aesthetic, health, or hygiene reasons, or to treat disease.
Preputioplasty is a procedure to relieve a tight foreskin without resorting to circumcision.
Other practices include genital piercings involving the foreskin and slitting the foreskin
The word frenulum on its own is often used for the frenulum preputii penis, which is an elastic band of tissue under the glans penis that connects to the prepuce, or foreskin, and helps contract the prepuce over the glans. It may be partially or totally removed during the style of hospital circumcision practiced in various countries.
Frenulum breve is the condition in which the frenulum of the penis is short and restricts the movement of the prepuce, and may or may not interfere with normal sexual activity. The condition can be treated by frenuloplasty, frenectomy, or circumcision, but recently, frenulum breve has been treated with the use of corticosteroid creams and manual stretching of the frenulum. The frenulum may be entirely missing in cases of first degree Hypospadias.[
The glans penis is the sensitive erectile tip of the penis. It is wholly or partially covered by the foreskin, except when the foreskin is retracted, such as during sexual intercourse while the penis is erect, or when the foreskin has been removed by circumcision.
The meatus (opening) of the urethra is at the tip of the glans penis. In young boys who wear nappies (diapers), the meatal area of the glans penis is at risk from meatitis, meatal ulceration, and possibly meatal stenosis.
Inflammation of the glans penis is known as balanitis. It occurs in 3-11% of males, and up to 35% of diabetic males. It has many causes, including irritation, or infection with a wide variety of pathogens.
The spermatic cord is the name given to the cord-like structure formed by the vas deferens and surrounding tissue (veins, arteries, nerves, and lymphatic vessels) that run from the abdomen down to each testicle.
The spermatic cord is sensitive to torsion, in which the testicle rotates within its sac and kinks off its own blood supply. Testicular torsion may result in irreversible damage to the testicle within hours.
In anatomy, the urethra is a tube, which connects the urinary bladder to the outside of the body. The urethra has an excretory function in both sexes, to pass urine to the outside, and also a reproductive function in the male, as a passage for sperm.
The external urethral sphincter is a striated smooth muscle that allows voluntary control over urination. Men have a longer urethra than women. This means that women tend to be more susceptible to infections of the bladder (cystitis) and the urinary tract. The length of a male's urethra, and the fact it contains a number of bends makes catheterization more difficult.
In the human female, the urethra is about 1-1.5 inches (2.5-4 cm) long and opens in the vulva between the clitoris and the vaginal opening. In the human male, the urethra is about 8 inches (20 cm) long and opens at the end of the penis.
The urethra is divided into three parts in men, named after the location:
The prostatic urethra crosses through the prostate gland. There is a small opening where the vas deferens enters.
The membranous urethra is a small (1 or 2 cm) portion passing through the external urethral sphincter. This is the narrowest part of the urethra.
The spongy (or penile) urethra runs along the length of the penis on its ventral (underneath) surface. It is about 15-16 cm in length, and travels through the corpus spongiosum.
Medical problems of the urethra
Hypospadias and epispadias are forms of abnormal development of the urethra in the male, where the opening is not quite where it should be (it occurs lower than normal with hypospadias, and higher with epispadias). A chordee is when the urethra develops between the penis and the scrotum.
Infection of the urethra is urethritis, said to be more common in females than males. Urethritis is a common cause of dysuria (pain when urinating).
Related to urethritis is so called urethral syndrome
Passage of kidney stones through the urethra can be painful and subsequently it can lead to urethral strictures
Endoscopy of the bladder via the urethra is called cystoscopy.
The vas deferens, also called ductus deferens, (Latin: "carrying-away vessel") is part of the human male anatomy. There are two of them; they are muscular tubes (surrounded by smooth muscle) connecting the left and right epididymis to the ejaculatory ducts in order to move sperm. Each tube is about 30 centimeters long. During ejaculation the wall of the vas deferens thickens and thins itself, thus propelling the sperm forward. The sperm are transferred from the vas deferens into the urethra, collecting fluids from the male accessory sex glands en route.
Vasectomy is a method of contraception where the vasa deferentia are permanently cut.
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Chapter V - Male Reproduction