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Primary urethral groove | |
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Details | |
Precursor | Urogenital folds |
Gives rise to | Urethra |
Identifiers | |
Latin | sulcus urethralis primarius |
TE | urethral groove_by_E5.6.4.2.1.7.3 E5.6.4.2.1.7.3 |
Anatomical terminology |
The primary urethral groove or urethral groove is a temporary linear indentation on the underside (ventral side) of the male penis during embryonic development.
In humans, it typically appears around eight weeks of gestation and becomes closed into a normal male urethra by the twelfth week.
Failure of complete closure can be associated with hypospadias. [1]
The urethra is a tube that connects the mammalian urinary bladder to the urinary meatus. Male and female placental mammals release urine through the urethra during urination, but males also release semen through the urethra during ejaculation.
A urethral stricture is a narrowing of the urethra, the tube connected to the bladder that allows the passing of urine. The narrowing reduces the flow of urine and makes it more difficult or even painful to empty the bladder.
Hypospadias is a common variation in fetal development of the penis in which the urethra does not open from its usual location on the head of the penis. It is the second-most common birth defect of the male reproductive system, affecting about one of every 250 males at birth, although when including milder cases, is found in up to 4% of newborn males. Roughly 90% of cases are the less serious distal hypospadias, in which the urethral opening is on or near the head of the penis (glans). The remainder have proximal hypospadias, in which the meatus is all the way back on the shaft of the penis, near or within the scrotum. Shiny tissue that typically forms the urethra instead extends from the meatus to the tip of the glans; this tissue is called the urethral plate.
The urogenital sinus is a part of the human body only present in the development of the urinary and reproductive organs. It is the ventral part of the cloaca, formed after the cloaca separates from the anal canal during the fourth to seventh weeks of development.
Urethral sounding is the practice of inserting objects into the urethra for sexual gratification. Urethral dilatation is a urological procedure that uses probes called sounds to enlarge the inside diameter of the urethra and locate obstructions in the urethra, or as a treatment for urethral strictures.
The corpus spongiosum is the mass of spongy tissue surrounding the male urethra within the penis. It is also called the corpus cavernosum urethrae in older texts.
The male reproductive system consists of a number of sex organs that play a role in the process of human reproduction. These organs are located on the outside of the body, and within the pelvis.
The urethral or periurethral glands are glands that branch off the wall of the urethra of mammals. The glands secrete mucus and are most numerous in the section of the urethra that runs through the penis. Urethral glands produce a colloid secretion containing glycosaminoglycans; this secretion protects the epithelium against urine.
The urethral artery arises from the internal pudendal artery a branch of the internal iliac artery. The internal pudendal artery has numerous branches including the artery of the bulb of the penis immediately before the urethral and the dorsal artery of the penis more distally.
The northern red-sided opossum or the Guianan short-tailed opossum, Monodelphis brevicaudata, is an opossum species from South America. It is found in Bolivia, Brazil. French Guiana, Guyana, Suriname and Venezuela.
The spongy urethra is the longest part of the male urethra, and is contained in the corpus spongiosum of the penis.
The urethral crest is an anatomical feature present in the urinary system of both males and females.
In male anatomy, the lacuna magna is the largest of several recesses in the roof of the navicular fossa of the male urethra.
The urinary meatus, also known as the external urethral orifice, is the opening where urine exits the male and female urethra. It is where semen also exits the male urethra. The meatus has varying degrees of sensitivity to touch.
The development of the reproductive system is the part of embryonic growth that results in the sex organs and contributes to sexual differentiation. Due to its large overlap with development of the urinary system, the two systems are typically described together as the genitourinary system.
The urethral sphincters are two muscles used to control the exit of urine in the urinary bladder through the urethra. The two muscles are either the male or female external urethral sphincter and the internal urethral sphincter. When either of these muscles contracts, the urethra is sealed shut.
A retrograde urethrography is a routine radiologic procedure used to image the integrity of the urethra. Hence a retrograde urethrogram is essential for diagnosis of urethral injury, or urethral stricture.
The body or shaft of the penis is the free portion of the human penis that is located outside of the pelvic cavity. It is the continuation of the internal root, which is embedded in the pelvis and extends to the glans. It is made up of the two corpora cavernosa and the corpus spongiosum on the underside. The corpora cavernosa are intimately bound to one another with a dorsally fenestrated septum, which becomes a complete one before the penile crura. The body of the penis is homologous to the female clitoral body.
Urethral intercourse or coitus par urethra is sexual penetration of the female urethra by an object such as a penis or a finger. It is not to be confused with urethral sounding, the act of inserting a specialized medical tool into the urethra as a form of sexual or fetishistic activity.