Question

A fall in glomerular filtration rate (GFR) activates_________?​

Answer 1

A fall in GFR can activate the JG (Juxtaglomerular) cells to release renin which can stimulate the glomerular blood flow and thereby the GFR back to normal.

Answer 2

A fall in glomerular filtration rate (GFR) activates →Juxta - Glomerular cells to release renin

See my attachment for explanation

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