What are the homeostatic functions of the kidneys?
Maintenance of plasma volume and osmolarity
What do the kidneys excrete?
Drugs and their metabolites
What hormones do the kidneys secrete?
What are the functions of
a) Maintenance of BP by RAAS
b) Protects RBC from damage and increases RBC production - used in doping
What vitamin do the kidneys activate?
What is its active form called?
What is the name and function of activated Vitamin D?
Enables calcium absorption in GI tract
At what levels are the
a) left kidney
b) right kidney
a) T12 - L2 (not pushed inferiorly)
b) L1 - L3 (pushed inferiorly by liver)
What process propels urine from the kidneys to the bladders through the ureters?
What appearances do the renal cortex and medulla have?
Cortex - granulated
Medulla - striated
The renal medulla is arranged into ___ of nephrons.
How long is an adult kidney?
How much of the cardiac output do the kidneys account for?
loads, understandable given they filter the blood
What are the functional units of the kidneys?
arranged into pyramids in renal medulla
Which four processes occur in nephrons?
FILTRATION of urine from blood
REABSORPTION of water, ions, glucose, AAs from tubules into capillaries
SECRETION of "" from capillaries to tubules
EXCRETION into ureters
What blood vessels supply the nephrons?
Renal artery - splits into afferent and efferent arterioles
Stuff then reabsorbed into peritubular capillaries draining into Renal vein
What structure is the glomerulus found inside?
Where does filtration of blood occur?
Blood is filtered into Bowman's capsule
Where does urine travel from the glomerulus to reach the collecting duct?
Loop of Henle
What part of the distal tubule passes by the glomerulus and alters renal function?
Which structures does the juxtaglomerular apparatus pass between?
Afferent and efferent arterioles
Nephrons are split between the renal ___ and ___.
renal cortex and medulla
What are the two types of nephron found in the kidney?
Which type of nephron is more common?
What is the difference between cortical and juxtamedullary nephrons?
Juxtamedullary nephrons have:
- Longer Loops of Henle
- One single peritubular capillary called the vasa recta which follows the Loop of Henle
What type of capillaries do
b) juxtamedullary nephrons have?
a) Loads of peritubular capillaries
b) One vasa recta
Juxtamedullary nephrons produce more ___ urine.
concentrated / hypertonic
Which arteriole has the wider diameter?
What are podocytes?
Epithelial cells of Bowman's capsule, have big processes called filtration slits
What is found between the endothelium of glomerular capillaries and the podocytes of Bowman's capulse?
Basement membrane (no cells)
Which layers make up the glomerular membrane?
Endothelium of glomerular capillary
Podocytes of Bowman's capsule