A&P: The urinary system

what does the urinary system do?

controls the discharge waste materials filtered from the blood by the kidneys

• control fluid balance in body

• filter and eliminate wastes

• control pH balance

what do the kidneys do?

• get rid of blood of toxic waste products

• control the balance of water and salt

!!! nearly 20% of the output of blood from heart passes through the kidneys each minute, as large vessels attach the kidneys to the aorta and inferior vena cava

what are the ureters?

a small, hollow, muscular tube that passes from the renal pelvis of each kidney along the surface of the posterior abdominal wall behind the peritoneum

• drains into urinary bladder

what is peristalsis?

a wavelike contraction of smooth muscle that occurs in these tubes [also in digestive system in stomach] to move urine to the bladder

what is the urinary bladder?

an organ located immediately behind the pubic symphysis, composed of smooth muscle and a specialized lining membrane

• ureter enters posteriorly at base on either side

what is the urethra?

the bladder empties outside the body through the urethra