CBSE Class 10 Answered

The Human Urinary System consists of a pair of kidneys, a pair of ureters, urinary bladder and urethra.

A Pair of Kidneys: Dark red, bean shape, 10 cm long, 6 cm wide. The right kidney is slightly lower in position due to the presence of the liver. The renal artery supplies oxygenated blood to the kidneys. The renal veins take away deoxygenated blood from the kidneys. A Pair of Ureters: Ureters are tube-like structures that arise from the notch, i.e. hilum of each kidney. The front end of the ureters is somewhat expanded into each kidney and is called pelvis. The ureters connect behind with the urinary bladder. The ureters carry the urine produced to the urinary bladder. At its distal end, valves are present which prevent backflow of the urine into the ureters when the bladder contracts. Urinary Bladder: Muscular sac-like structure. It stores urine temporarily. Its opening is guarded by muscular sphincters. The sphincters open at the time of micturition (urination). Urethra: Short muscular tube which expels urine out of the body. It is long in males and very short in females. The opening is guarded by sphincters which open at the time of urination.