Excretory System Chapter 38-3

Kidney filters blood salt and water absorption located behind the intestines Ureter carries urine from kidney to bladder Bladder holds urine Urethra carries urine from bladder out of body

Nephron- functional unit of kidney

Kidneys Maintain Homeostasis HomeostasisHomeostasis –process of maintaining a stable internal environment Kidneys filter the blood to remove waste (sugars, amino acids, salts, drugs)Kidneys filter the blood to remove waste (sugars, amino acids, salts, drugs) Maintains water and salt balance in the bloodMaintains water and salt balance in the blood Maintains pHMaintains pH

How long does it take the kidney to filter the blood? About 45 minutes!About 45 minutes! Your blood passes through the kidneys 300 times a day.Your blood passes through the kidneys 300 times a day. Every day the kidney sends about six cups of urine to the bladder.Every day the kidney sends about six cups of urine to the bladder. The kidney has one million nephrons that filter the blood.The kidney has one million nephrons that filter the blood.

Kidney Stones Kidney stones are made of calcium, magnesium, and uric acid saltsKidney stones are made of calcium, magnesium, and uric acid salts Ultrasound waves break the stone into smaller fragments that can pass out of the bodyUltrasound waves break the stone into smaller fragments that can pass out of the body

Urinary Tract Infections Urine does not normally contain bacteria.Urine does not normally contain bacteria. Bacteria can enter the urinary tract from the skin around the rectum and genitals by traveling up the urethra into the bladder.Bacteria can enter the urinary tract from the skin around the rectum and genitals by traveling up the urethra into the bladder. The bacteria can infect and inflame the bladder and cause swelling and pain in the lower abdomen and side.The bacteria can infect and inflame the bladder and cause swelling and pain in the lower abdomen and side. If the bacteria travel up through the ureters to the kidneys, a kidney infection can develop.If the bacteria travel up through the ureters to the kidneys, a kidney infection can develop.

Dialysis Uses a machine to filter blood when the kidneys do not workUses a machine to filter blood when the kidneys do not work