Organs Sagittal (Male)
The ductus deferens, also known as the vas deferens, is a tiny muscular tube in the male reproductive system that carries sperm from the epididymis to the ejaculatory duct. There is a pair of these ducts in the male body, with one duct carrying sperm from each testis to the left and right ejaculatory ducts. Along the way they pass through the scrotum, spermatic cord, inguinal canal, and pelvic body cavity. The location and function of the ductus deferens makes it a prime area for male contraception surgery. The ductus deferens is a thin tubule less than a quarter of an inch (5 mm) in diameter, but more than one foot (30 cm) long. It begins as a continuation of the tail of the epididymis in the posterior region of the scrotum. Compared to the epididymis, the ductus deferens is much wider and less convoluted, with most of its folds at the transition between the two structures. From the epididymis, the ductus deferens ascends posterior to the testes and enters the spermatic cord that connects the testes to the rest of the body. It continues with the spermatic cord, exiting the scrotum and entering the pelvic body cavity at the inguinal canal. Inside the pelvic cavity, the ductus deferens passes anterior to the pelvic bone before turning about 90 degrees toward the posterior and passing over the pelvic brim toward the urinary bladder. It continues around the side of the bladder and passes superior to the ureters before turning 90 degrees toward the inferior direction and descending along the posterior end of the bladder to the prostate gland. Between the ureters and the prostate, the ductus deferens expands its diameter considerably in a region known as the ampulla before narrowing and joining with the seminal vesicles at the ejaculatory duct inside the prostate. Source
The pubic symphysis is a cartilaginous connection between the left and right pubic bone and therefor between the left and right hip bone. Being made of cartilage, it functions as a joint. During pregnancy, hormones cause the pubic symphysis to be more flexible, thereby facilitating an easier delivery. For men the pubic symphysis has the function of suspending the penis, keeping it upright when erect. Source
The urinary bladder is a muscular sac in the pelvis, just above and behind the pubic bone. When empty, the bladder is about the size and shape of a pear. Urine is made in the kidneys and travels down two tubes called ureters to the bladder. The bladder stores urine, allowing urination to be infrequent and voluntary. The bladder is lined by layers of muscle tissue that stretch to accommodate urine. The normal capacity of the bladder is 400 to 600 mL. During urination, the bladder muscles contract, and two sphincters (valves) open to allow urine to flow out. Urine exits the bladder into the urethra, which carries urine out of the body. Because it passes through the penis, the urethra is longer in men (8 inches) than in women (1.5 inches). Source
The corpus cavernosum contains spongy erectile tissue. Cavernosal arteries run along the middle of each corpus cavernosa. The function of the corpus cavernosum is to facilitate penile erections. Muscles surround the cavernosum and spongiosum. These muscles support the penis when erect and contract during ejaculation. To achieve erection the brain sends impulses to the nerves in the penis and these cause the multiple muscles around the corpus cavernosum penis to relax. This allows blood to flow in to the open spaces inside the corpora cavernosa. This blood creates pressure making the penis expand, which then compresses the veins that normally allow blood to drain. Once the blood is trapped, a muscle located in the corpora cavernosa helps to sustain the erection. An erection is reversed once the muscles in the penis contract preventing blood flow in to the corpora cavernosa.
While urine and semen travel through the urethra, the tube is not solely responsible for moving fluids. The urethral sphincter controls both voluntary and involuntary urination. This group of muscles includes both the internal and external sphincter muscles of the urethra. The bulbospongiosus muscle of the penis plays an active role in ejaculation. The male urethra is comprised of four main segments. The preprostatic urethra runs in front of the prostate, while the prostatic urethra courses through that gland. The membranous urethra travels through the external urethral sphincter, while the spongy urethra travels the length of the penis and terminates at the meatus at the tip of the sexual organ. Source
The corpus spongiosum of penis is a mass of erectile tissue that lies along the underside of the penis and is located below the pair of corpus cavernosa, which contain 90 percent of the blood volume during a normal erection. It is a smaller region compared to either of the identical corpus cavernosa. The three groups of tissues, the two cavernosa and the spongiosum, are expandable, sponge-like structures involved in the process of a penile erection. The corpus spongiosum penis corresponds to the female vestibular bulbs. It contains the urethra, the tube through which urine and semen exit the body, and extends to form the glans penis, an expanded cap at the tip of the penis. The corpus spongiosum penis may be described as enclosing the urethra and ends at the vertical urethral orifice. This third mass of tissue mainly prevents compression of the urethra during penile erection. Source
The glans penis can be described as the rounded head (or tip) of the penis. Located in the middle of the glans penis is the opening of the urethra, the tube through which semen and urine exits the body. Often referred to as the penis’s ‘head,’ the term glans penis was derived from the Latin word for ‘acorn.’ This nickname was chosen due to the acorn-like shape of the glans of the penis. At birth, the glans of the penis is attached to an area of skin called the foreskin. Over time, this foreskin will begin to separate from the glans, until the skin is able to full retract. This separation occurs slowly and naturally and could take as long as eighteen years to separate fully. In children who are circumcised, most of the foreskin is removed, leaving the glans exposed at all times. Circumcised children are at an increased risk for infections of the urethra opening (or meatus), such an illness is referred to as urethritis. Alternately, parents of uncircumcised children should gently clean the glans area daily to prevent bacteria growth. Source
The fold of skin that covers the head of the penis (foreskin). Source
Ampulla Prostate Gland
Each of these branched tubular glands lined by simple columnar epithelium is an enlargement of the ductus deferens in its terminal portion. These are typical tubular glands in ruminants, horses and dogs; absent in the cat and poorly developed in boars. The function of the white serous secretion is not known.
The anus is the last part of the digestive tract. It is a 2-inch long canal consisting of the pelvic floor muscles and the two anal sphincters (internal and external). The lining of the upper anus is specialized to detect rectal contents. It lets you know whether the contents are liquid, gas, or solid. The anus is surrounded by sphincter muscles that are important in allowing control of stool. The pelvic floor muscle creates an angle between the rectum and the anus that stops stool from coming out when it is not supposed to. The internal sphincter is always tight, except when stool enters the rectum. It keeps us continent when we are asleep or otherwise unaware of the presence of stool. When we get an urge to go to the bathroom, we rely on our external sphincter to hold the stool until reaching a toilet, where it then relaxes to release the contents. Source
The epididymis is a long, coiled tube that stores sperm and transports it from the testes. It appears as a curved structure on the posterior (back) margin of each testis. It is comprised of three sections. These are the head, body, and tail. Although it bears some superficial resemblance to the testes, the epididymis differs in that it is smaller, and the tubes are larger and less densely packed. Near the top of the testis is the head of the epididymis, which stores sperm until it is ready to undergo maturation. Next is the body, a long, twisted tube where the sperm matures. This maturation takes approximately one week. Last is the tail, which connects to the deferent duct, also referred to as the ductus deferens or vas deferens. From here, the sperm is transported to the ejaculatory duct. Partially surrounding and separating the epididymis from the testis is a thin sheet of tissue referred to as the tunica vaginalis. The walls of the epididymis are lined in pseudostratified columnar epithelial tissue, meaning that the arrangement of the cells gives the appearance of two layers, although it is only one. Source
The scrotum is the loose pouch-like sac of skin that hangs behind the penis. It contains the testicles (also called testes), as well as many nerves and blood vessels. The scrotum has a protective function and acts as a climate control system for the testes. 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. Source
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. Source