The perineal raphe is a visible line or ridge of tissue on the body that extends from the
anus
In mammals, invertebrates and most fish, the anus (: anuses or ani; from Latin, 'ring' or 'circle') is the external body orifice at the ''exit'' end of the digestive tract (bowel), i.e. the opposite end from the mouth. Its function is to facil ...
through the
perineum
The perineum (: perineums or perinea) in placentalia, placental mammals is the space between the anus and the genitals. The human perineum is between the anus and scrotum in the male or between the anus and vulva in the female. The perineum is ...
to the
scrotum
In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin ...
(male) or the
vulva
In mammals, the vulva (: vulvas or vulvae) comprises mostly external, visible structures of the female sex organ, genitalia leading into the interior of the female reproductive tract. For humans, it includes the mons pubis, labia majora, lab ...
(female). It is found in both males and females, arises from the fusion of the
urogenital folds
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 typicall ...
, and is visible running medial through anteroposterior, to the anus where it resolves in a small knot of skin of varying size.
In males, this structure continues through the midline of the scrotum (scrotal raphe) and upwards through the posterior midline aspect of the
penis
A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate.
The term ''pen ...
(
penile raphe). It also exists deeper through the scrotum where it is called the
scrotal septum
The septum of scrotum or scrotal septum is an incomplete vertical wall (septum) that divides the scrotum into two compartments –each containing a single testis. It consists of flexible connective tissue and nonstriated muscle (dartos fascia
...
. It is the result of a
fetal
A fetus or foetus (; : fetuses, foetuses, rarely feti or foeti) is the unborn offspring of a viviparous animal that develops from an embryo. Following the embryonic stage, the fetal stage of development takes place. Prenatal development is a ...
developmental phenomenon whereby the scrotum and penis close toward the midline and fuse.
See also
*
Embryonic and prenatal development of the male reproductive system in humans
*
Frenulum of penis
*
Linea nigra
*
Raphe
Raphe ( ; from ;Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. : raphae or raphes) has several differe ...
Images
File:Gray1119.png, Stages in the development of the external sexual organs in the male and female
File:Raphe1 Labels.jpg, Perineal and scrotal raphe
File:Perineal raphe in female.jpg, Perineal raphe in female
References
Scrotum
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