Renal system Flashcards
Name the parts of a nephron
What do the afferent and efferent arterioles do?
Afferent arterioles bring blood into your kidney’s glomerulus (blood vessels that filter your blood). Afferent arterioles can dilate, or get wider, to allow for more filtration. Efferent arterioles take blood out of your glomerulus.
What is the function of the glomerulus and bowmans capsule and how does it work?
blood comes in from the renal artery, then into the afferent arteriole, being filtrated in the glomerulus through small pores, while the filtrated blood being carried into the efferent arteriole (and then the renal vein), the waste products and extra ions are being caught by the bowman’s capsule and transported to the rest of our nephron.
What is the function of the proximal convoluting tubule?
The main function of the PCT is to reabsorb water and solutes like sodium, which is transported back into the blood
Function of the ascending and descending loop of Henle?
Tubular reabsorption.
Descending limb - water is reabsorbed
Ascending limb - Na+ is reabsorbed
Function of the distal convoluting tubule and collecting duct?
Controlled salt reabsorption dependant on level of aldosterone.
DCT + CD is where hormones act to maintain fluid homeostasis.
ADH increases water permeability of the collecting duct, allowing to make concentrated urine.
What is anuria?
Anuria is the absence of urine production, defined as a urine output of fewer than 100 milliliters per day.This can happen as a result of conditions like shock, severe blood loss and failure of your heart or kidneys. It can also be due to medications or toxins.
What is oliguria?
Oliguria is defined as urinary output less than 400 ml per day or less than 20 ml per hour
What is polyuria?
Excessive urination volume (or polyuria) occurs when you urinate more than normal. Urine volume is considered excessive if it equals more than 2.5 liters
What is the function of juxtaglomerular cells?
Juxtaglomerular cells are responsible for the production, storage, and release of a hormone called renin which regulates blood pressure.
They are also called granular cells as they have a large amount of renin-secreting granules. They sense the blood pressure in the arteriole and release an adequate amount of renin.
What are macula densa cells?
Located at DCT and end of ascending limb of loop of henle.
Salt sensors that generate paracrine chemical signals in the juxtaglomerular apparatus
Renin secretion depends on NaCl delivery to and reabsorption by the macula-densa cells
What are extra glomerular cells?
Extra glomerular cells remove trapped residue, etc. from the glomerular basement membrane and filtration slit diaphragm and so maintain these structures free of debris.
Secrete molecules that assist in response to glomerular injury
List 7 main functions of the kidneys
Remove waste products
Remove drugs
Fluid homeostasis
Release hormones (ADH and renin)
Control production of RBC
Produce vitamin D
Electrolyte balance
Difference between juxtamedullary and cortical nephrons?
Juxtamedullary: 15% of nephrons
Cortical: 85% of nephrons
Juxtamedullary have a larger glomerulus and loop of henle - they have a bigger role in urine concentration
Name where which diuretics work
