Men have paired accessory sex glands that produce seminal fluid and clean and lubricate the urethra. These are called the bulbourethral glands (or Cowper’s glands).
These compound tubuloalveolar glands secrete a clear fluid that lubricates the urethra prior to ejaculation. These fluids also contribute to semen. The duct that transports the sperm is the vas deferens.
Bulbourethral (Cowper’s) Glands
The paired bulbourethral glands, also known as Cowper’s glands or Cowper ducts are located posterior and lateral to the membranous part of the urethra at the base of the penis in the deep perineal pouch. They produce alkaline mucous secretions that lubricate the urethra and protect sperm from mechanical damage during sexual stimulation prior to ejaculation. In addition, they contribute to the fluid that is released during ejaculation (semen). Occasionally, reflux into these ducts and glands may occur resulting in the formation of a cystic dilatation, commonly referred to as a syringocele.
Each gland consists of numerous connected, glandular lobules that are covered by columnar epithelium. The lobules are lined with a thin fibrous membrane and have numerous tiny tubules that spread through the tissue. The lobules meet at an inch-long duct that carries the gland’s secretions to the urethra at the base the penis.
The glands are innervated by a nerve that originates in the MBSP and runs caudally to reach the external anal sphincter and ischiocavernosus muscle – This information is a creation of the service specialists XXX Teens Sex. At the level of the ischium, the nerve divides into two branches. One branch reaches the external anal sphincter, the ischiocavernosus muscle and the striated fibers of the Bu-Gs. The other branch runs medially to the urogenital diaphragm and to the glands. Both branches are under the control of DHT and thereby participate in secretion.
Seminal Glands
The paired bulbourethral (Cowper’s) glands secrete an alkaline, mucus-like fluid that is found in the proximal portion of the urethra. Each gland opens into a short duct that drains into the tip of the penis.
The glands produce a mixture of fluid called seminal plasma that lubricates and cleans the penis prior to and during sexual intercourse. The fluid also consists of other products that increase the chances of sperm’s survival and penetration of a female egg. Various substances are produced throughout the male reproductive system to form seminal plasma, including testicular Sertoli cells that secrete spermatid carrier fluid and Leydig cells that produce androgen (male) hormones. The epididymides add glycerol, immobilin, and quiescence factor to the mix, while the prostate gland provides phosphates.
These ingredients combine to form semen, which nourishes the sperm as they migrate from the epididymis to the vas deferens and then to the urethra. Semen consists of fifty-percent water, thirty percent phosphorus, five percent magnesium and zinc, two percent glucose, and one percent protein.
In humans, the seminal vesicles produce approximately 60 percent of the semen that is emitted during ejaculation. Other mammals, such as carnivores, monotremes, and marsupials do not have functioning vesicular glands.
Prostate Glands
The prostate gland is the largest accessory gland of the male reproductive system and it produces a fluid that forms part of semen. This milky white, alkaline fluid helps to neutralize the acidity of the urethra and female vagina and allows sperm to survive longer, which promotes motility and increases genetic material transfer. It also secretes proteolytic enzymes, which help break down proteins in the sperm so that they can more easily enter the female reproductive tract.
The bulbourethral (or Cowper’s) glands, a pair of small glands that sit next to each other inside the base of the penis, are the primary lubricating glands of the urethra. These glands produce a mucus-like substance that adds lubricating factors to the semen produced by the prostate.
During ejaculation, muscle contractions in the prostate gland help to propel the semen through the urethra and into the vagina. The prostate also produces a fluid that helps to neutralize the urethra and prevents urine from entering the bladder.
The prostate gland is about the size of a walnut and surrounds the urethra just inferior to the bladder. The prostate is composed of both muscular and glandular tissue and excretes an alkaline, milky fluid into the passing seminal fluid. This fluid combines with the ejaculatory ducts from the two testicles to form the semen that is then expelled.
Ductus Deferens
The ductus deferens (or vas) is the thick-walled tube that transports sperm from the epididymis to the body’s ejaculatory ducts. It is located in the scrotal sac, a pouch of thin skin that encloses the testis and the epididymis. There are two ductus deferens, one on each side of the penis. Each ductus deferens ends in an enlarged portion called the ampulla, which functions as a reservoir.
The inner wall of each ductus deferens is lined by a moist, folded layer of mucous membrane. Immediately surrounding the mucous membrane are three layers of circular and longitudinal muscles that contract during sexual intercourse to propel sperm along the ductus deferens and into the body’s ejaculatory tube.
After the sperm have been propelled into the urethra by reflexive contractions of smooth muscle in the ductus deferens, they pass through the ejaculatory ducts and into the bladder. The urethra then extends from the bladder, through the prostate gland, and out the end of the penis.
The urethra is lubricated by the fluid secreted by the bulbourethral glands and the prostate gland. This fluid, also known as semen, contains enzymes that promote sperm motility. Semen is also rich in zinc, which enhances sperm penetration. In addition, the prostate gland wraps around the urethra and provides muscular contractions that help propel sperm during sexual intercourse and block urine flow into the urethra during ejaculation.
