Urinary bladder

Urinary bladder
1. Human urinary system: 2. Kidney, 3. Renal pelvis, 4. Ureter, 5. Urinary bladder, 6. Urethra. (Left side with frontal section) 7. Adrenal gland Vessels: 8. Renal artery and vein, 9. Inferior vena cava, 10. Abdominal aorta, 11. Common iliac artery and vein With transparency: 12. Liver, 13. Large intestine, 14. Pelvis
Details
Precursor	urogenital sinus
System	Urinary system
Artery	Superior vesical artery Inferior vesical artery Umbilical artery Vaginal artery
Vein	Vesical venous plexus
Nerve	Vesical nervous plexus
Identifiers
Latin	vesica urinaria
MeSH	A05.810.161
TA	A08.3.01.001
FMA	15900
Anatomical terminology []

The urinary bladder is a hollow muscular organ that collects urine from the kidneys before disposal by urination. A hollowmuscular, and distensible (or elastic) organ, the bladder sits on the pelvic floor. Urine enters the bladder via the ureters and exits via the urethra. The typical human bladder capacity is between 300 and 500 mL (10.14 and 16.91 fl oz).

The bladder is a hollow muscular organ situated at the base of the pelvis. Urine collects in the bladder from the two ureters, which open into the bladder at its back and connect to the kidneys. Urine leaves the bladder via the urethra, a single muscular tube which ends in the urethral orifice. Anatomically, the bladder is divided into a fundus at the top, two ureteric orifices, and an opening for the urethra which surrounds the trigone of the bladder. In men, the prostate gland lies outside the opening for the urethra.

The bladder is situated below the peritoneal cavity near the pelvic floor. In men, it lies in front of the rectum, separated by a space. In women, it lies in front of the uterus.

The outside of the bladder is protected by a serous membrane. The bladder wall itself is smooth muscle. The inner side of the bladder is lined with a mucosal membrane consisting of a surface glycocalyx that protects the cells beneath it from urine, the urothelium (a form of transitional epithelium), a basement membrane, and the sub-urothelium.

Vertical section of bladder wall.