Organs and atomic structures of the urinary system

Kidney

One of two bean-shaped organs located on each side of the vertebral column on the posterior wall of the abdominal cavity anteriorly by the parietal peritoneum. Their function is to remove waste products from the blood and to aid in maintaining water and electrolyte balances.

Nephron

Urine-producing microscopic structure. Approximately 1 million nephrons are located in each kidney.

Glomerulus (pl. glomeruli)

Cluster of capillaries at the entrance of the nephron. The process of filtering the blood, thereby forming urine, begins here

Renel pelvis

Funnel-shaped reservoir in the kidney that collects the urine and passes it to the ureter

Hilum

Indentation on the medial side of the kidney where the renal artery, vein, and pelvis are located in the ureter leaves the kidney

Ureters

Two slender tubes, approximately 10 to 13 inches (26 to 33 cm) long, that receive the urine from the kidneys and carry it to the posterior portion of the bladder

Urinary bladder

Muscular, hollow organ that temporarily holds the urine. As it fills, the thick, muscular wall becomes thinner, and the organ increases in size.

Urethra

Lowest part of the urinary tract, through which the urine passes from the urinary bladder to the outside of the body. This narrow tube varies in length by sex. It is approximately 1.5 inches (3.8 cm) long in the female and approximately 8 inches (20cm) in the male, and whom it is also part of the reproductive system. It carries seminal fluid (semen) at the time of ejaculation.

Urinary meatus

Opening through which the urine passes to the outside