3.1 Clearance and Filtration Flashcards
List some differences between cortical nephrons and juxtamedullary nephrons
Cortical: outer cortex, small glomerulus, short loop of Henle
Juxtamedullary: inner cortex, large glomerulus, lomg loop of Henle
How much blood is filtered by the glomerulus at any 1 point?
20%
What substances move throught the glomerular membrane?
Water
Salts
Small molecules
Name the 3 layers of the filtration barrier in the kidney
Capillary endothelium
Basement membrane
Podocyte layer
What pressures are involved in filtration of blood in the kidney?
Hydrostatic pressure in capillary
Hydrostatic pressure in Bowman’s capsule
Oncotic pressure difference between capillary and tubular lumen
How is filtration rate in the kidney autoregulated?
Increased blood pressure- afferent arteriole constricts
Decreased blood pressure- afferent arteriole dilates
How is increased blood pressure detected by the kidney?
Macula densa cells in the DCT detect increased levels of Na+ and Cl-
What chemical is released if the DCT detects that blood pressure is too high?
Adenosine
What chemical is released if the DCT detects that blood pressure is too low?
Prostaglandins
What ions are reabsorbed in the PCT?
Na+ via Na-K-ATPase
How is glucose reabsorbed in the PCT?
Co-transport with Na+
How much glucose is reabsorbed in the PCT?
100%
Pathological to find glucose in urine
What is a secondary way of secreting substances that do not move through the glomerulus?
Transepithelial transport mechanisms
Name some substances which arefiltered through the kidney via transepithelial transport mechanisms
Protons
Potassium
Organic cations or anions
What is exchanged in organic cation secretion in the PCT?
H+
