mucous glands, called
which secrete mucus
into the urethral canal
In a female, the urethra is about 4 centimeters long. It
passes forward from the bladder, courses below the symphy-
sis pubis, and empties between the labia minora. Its open-
external urethral orif
(urinary meatus), is anterior
to the vaginal opening and is about 2.5 centimeters posterior
to the clitoris
(f g. 20.32
In a male, the urethra, which functions both as a urinary
canal and a passageway for cells and secretions from the
reproductive organs, can be divided into three sections: the
prostatic urethra, the membranous urethra, and the penile
urethra (see F
and reference plate 20).
is about 2.5 centimeters long and
passes from the urinary bladder through the
located just below the bladder. Ducts from reproductive
structures join the urethra in this region.
Light micrograph of the human urinary bladder
Cross section through the urethra (10×).
Urinary bladder and urethra (
) of the female
(longitudinal section) and (
) of the male (longitudinal section).
Lumen of urethra