<prompt> What would tend to decrease GFR by more than 10 in a normal kidney?Decrease in renal aerial pressure from 100 to 85 mm Hg50 decrease in afferent aeriolar resistance50 decrease in efferent aeriolar resistance50 increase in the glomerular capillary filtration coefficient  <response>: 50 reduction in efferent aeriolar resistance would cause a large decrease in GFR--greater than 10. A decrease in renal aery pressure from 100 to 85 mm Hg would cause only a slight decrease in GFR in a normal, autoregulating kidney. A decrease in afferent aeriole resistance, a decrease in plasma colloid osmotic pressure, or an increase in the glomerular capillary filtration coefficient would all tend to increase GF 