The accessory ducts involved in sperm maturation and transportation include the epididymides, vasa deferentia, ejaculatory ducts, and urethra. These ducts play a critical role in the maturation, storage, and transportation of sperm from the testes to the urethra, where it is then released during ejaculation.
The epididymis is a small, comma-shaped organ located at the back of each testicle. The epididymis can be divided into three main parts: the head, body, and tail. The head of the epididymis is connected to the efferent ductules of the testis, which carry sperm from the testes. The tightly coiled epididymis tube, approximately 7 meters long when uncoiled, is where the sperm mature and become motile. The tail of the epididymis becomes less convoluted and gradually increases in diameter to become continuous with the vas deferens.
The vas deferens, or ductus deferens, is a 45-cm-long tube that passes through the inguinal canal. It curves along the lateral surface of the urinary bladder before merging with the duct from the seminal vesicle to form the ejaculatory duct.
The ejaculatory duct is a short, 2 cm-long tube that connects the vas deferens to the urethra. During ejaculation, the seminal fluid produced in the seminal vesicles and prostate gland mixes with spermatozoa and is expelled through the urethra.
In addition to sperm maturation and transportation, these ducts also recycle damaged sperm and absorb the fluid produced by the seminiferous tubules.
The paired seminal and bulbourethral glands and the single prostate gland comprise the accessory male reproductive glands.
The 5-centimeter-long seminal glands lie on the posterior wall of the bladder.
Their extensively folded mucosa forms a honeycomb labyrinth that secretes and stores an alkaline, viscous fluid rich in fructose, prostaglandins, and clotting proteins.
Contraction of the external capsule empties the secretion into the ejaculatory duct.
The prostate is a small, rounded organ about 4 cm in diameter surrounding the proximal end of the urethra.
It is made of smooth muscle fibers enveloping 30 to 50 compound tubulo-alveolar glands, producing the prostatic fluid.
This slightly acidic fluid is rich in enzymes that prevent sperm coagulation in the vagina.
The bulbourethral glands, also known as Cowper's glands, are small mucous glands measuring 10 millimeters.
They secrete a thick, alkaline mucus that neutralizes urinary acids in the urethra and lubricates the tip of the penis.
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