Urinary System

Question 1

What are the three parts of the kidneys?

Answer 1

Renal cortex - portions extend into the renal medulla (renal columns)

Renal medulla - consists of several cone-shaped sections (renal pyramids)

Renal hilum - entry/exit point for the: Ureter, renal blood vessels, nerves and lymphatic vessels

Question 2

What are diuretics?

Answer 2

Diuretics are substances that lead to decreases reabsorption of H2O and therefore, increases urine production

Question 3

What are urters?

Answer 3

25-30 cm long tubes that transport urine from the kidneys to the urinary bladder

They can also serve as a route for pathogens into the kidneys (ie. kidney infection)

Question 4

What are the functions of the urinary system?

Answer 4

Eliminates wastes (urine)

Regulates blood ionic composition (eg. Ca++)

Regulates blood volume and blood pressure

Regulates acid-base balance of the body

Secrete erythropoietin (EPO), which stimulates the production of RBCs in red bone marrow

Produces the active from of vitamin D (along with the liver)

Question 5

How does sympathetic nervous system impact the urinary system?

Answer 5

Relaxation of smooth muscle in the bladder wall and contraction of internal urethral sphincter - prevents urination

Vasoconstriction of afferent arterioles - decreased urine production

Question 6

How does parasympathetic nervous system impact the urinary system?

Answer 6

Contraction of smooth muscle in the bladder wall and relaxation of the internal urethral sphincter - causes urination