Glomerular Filtration Flashcards
What are the 3 processes forming urine?
Filtration, Reabsorption, Secretion
*Remember excretion happens at the end BUT is not involved in actually “forming” urine
What’s the major difference between glomerular filtrate and plasma?
filtrate doesn’t have very much protein
but like plasma its made of inorganic ions and low molecular-weight organic solutes in virtually same concentrations as in plasma
Substances in filtrate that are in the same concentration as in plasma are _________ ________?
FREELY FILTERED!
What substances are freely filtered?
many low-molecular-weight blood components: ions (Na, K, Cl, HCO3), neutral organics (glucose, Urea), Amino Acids, peptides (insulin and ADH)
What is GFR?
Glomerular Filtration Rate = volume of filtrate made per unit time
Normal: 125 ml/min = 180L/day
Range: 120-125 ml/min
What’s the avg total volume of plasma in humans?
3L
What’s the difference between normal net filtration of fluid across capillaries vs. GFR?
Normal amount fluid filtered by other capillaries: 4L/day
GFR = 180L/day
How often does the kidney filter plasma in a day?
60 times!
What’s not filtered by your glomerulus?
Red blood cells
Most plasma proteins
Where is plasma filtered?
Glomerulus
What is net filtration pressure?
Algebraic sum of HP and Osm Pressures from protein (oncotic or colloid osmotic pressure)
What are the 4 filtration pressures and which one isn’t present in the kidneys?
HP Bowman’s Capsule
HP Glomerulus
Oncotic Pressure BC
Oncotic Pressure Glomerulus
Oncotic Pressure of BC is NOT present
