Chapter 19: The Kidneys Flashcards
what are the functions of the urinary system?
- Regulate plasma ionic composition
- Regulate plasma volume
- Regulate plasma osmolarity
- Regulate plasma pH
- Remove metabolic waste products and foreign substances from plasma (creatinine, uric acid, urobilinogen, xenobiotics)
what are other functions of the urinary system?
- Secrete erythropoietin and renin
- Activate vitamin D3 to calcitriol
- Gluconeogenesis
-form urine
-located retroperitoneally
at the level of the lower ribs.
kidneys
transport urine from kidneys to bladder
ureters
store urine
bladder
excrete urine from bladder to outside of body
urethra
functional unit of kidney
nephron
consists of glomerulus and Bowman’s capsule
renal corpuscle
capillary network for filtration
glomerulus
- Receives the filtrate
- Inflow to renal tubules
Bowman’s capsule
what are the parts of renal tubules?
- proximal tuble
- loop of Henle
- distal convoluted tubule
- collecting duct
consists of descending limb, thin ascending limb, and thick ascending limb
Loop of Henle
divided into an outer cortex and an inner medulla
the kidney in cross section
flows into the renal pelvis prior to passing through the ureter into the bladder
urine leaving the nephrons
- enter the kidney at the hilus
- receive 20% of cardiac output at rest
- function is to filter blood
- account for 16% of ATP usage by the body
- take blood to the cortex
renal arteries
exit at the hilus
renal veins
- short loop of henle
- most numerous, 80-85%
- produce urine
cortical nephrons
- long loop of henle extends into medulla
- responsible for the medullary osmotic gradient
- produce urine
juxtamedullary nephron
contains all bowmans capsules, proximal and distal tububles
cortex
contains loops of henle and collecting ducts
medulla
has two arterioles and two sets of
capillaries that form a portal system
one nephron
from glomerulus to Bowman’s capsule
glomerular filtration
from tubules to peritubular capillaries
reabsorption
from peritubular capillaries to tubules
secretion