Urinary system Flashcards
Filter blood and form urine
Kidneys
Transport urine from kidneys to urinary bladder
Ureters
Collects and stores urine
Urinary bladder
What are the functions of kidneys
Contribute to homeostasis as excretory organs
Maintain the composition, pH, and volume of body fluids within normal limits
Remove metabolic wastes and substances present in excess, including foreign substances like drugs and their toxic metabolites
Secrete hormones that regulate specific metabolic processes
behind the parietal peritoneum
Retroperitoneal
Which kidney is higher than the other one?
Left kidney is 1.5 to 2 cm higher than right kidney
What surrounds the kidneys?
renal capsule, adipose tissue (renal fat), and connective tissue (renal fascia)
Hollow chamber in medial depression
Renal sinus
Outer region of kidney
Renal cortex
Inner region; composed of renal pyramids
Renal medulla
Extensions of cortex that dip into medulla
Renal columns
Entrance to the renal sinus
Hilum
Funnel-shaped sac; superior end of ureter
Renal pelvis
Large tubes that merge to form renal pelvis
Major calyces
Small tubes that merge to form major calyces
Minor calyces
Fibrous capsule around kidney
Renal capsule
Functional units of kidney, each of which is a site of urine production
Nephrons
stimulates red blood cell production
Erythropoietin
which helps to increase blood pressure
Renin
calcitriol (vitamin D)
increases calcium absorption from small intestine when blood calcium level is low
What happens when the kidneys are not functioning properly, who filters the blood?
Hemodialysis and Continuous peritoneal dialysis
Branch off cortical radiate arteries; each enters a different nephron
Afferent arteriole
Capillary cluster that branches from afferent arteriole; filters blood in each nephron
Glomerulus
Arises from merging of glomerular capillaries; transports blood that was not filtered by glomerulus
Efferent arteriole
Branches off the efferent arteriole; surrounds renal tubules
Peritubular capillaries
Venous draining from kidneys
From the nephron, blood flows into the renal vein, and leaves the kidney
Veins (parallel arteries of the same name), Cortical radiate (interlobular) vein, Arcuate (arciform) vein, Interlobar vein, Renal vein
There are no Segmental veins
Functional unit of the kidney (about 1 million in each kidney)
Nephron
Capillary cluster; filters blood to begin urine formation
Arises from afferent arteriole, drains into efferent arteriole
Renal corpuscle
Extends from glomerular capsule to collecting duct
Filtrate proceeds from Glomerular Capsule → Proximal tubule → Nephron loop (loop of Henle, composed of a descending and an ascending limb) → Distal tubule
Distal tubules of several nephrons empty into a collecting duct
Collecting duct continues through the medulla and drains through the renal papilla into a minor calyx
Renal tubule
Majority of nephrons (85%)
Lie almost completely in renal cortex
Have short nephron loops
Renal corpuscles located near surface of kidney
Cortical nephrons
Smaller percentage of nephrons (15%)
Have long nephron loops, that extend deep into medulla
Renal corpuscles lie deep in renal cortex
Important in regulating water balance and urine concentration
Juxtamedullary nephrons
A structure that regulates the secretion of the enzyme renin
Monitors and adjusts blood pressure and NaCl content of filtrate
Found at point of contact, where ascending limb of the nephron loop passes between the afferent and efferent arterioles
At this point of contact, cells of both structures are specialized
Juxtaglomerular Apparatus
Tall, closely packed cells of the ascending limb
Monitor NaCl content of filtrate
Mascula densa
Large, vascular smooth muscle cells of afferent arteriole
Monitor blood pressure
Juxtaglomerular cells