In a biology class related to excretion in the human body, a student gave an opinion that in every minute about 2% of total blood volume is coverted into GFR Whereas only 1% of GFR is eliminated as urine. Evaluate this opinion and substantiate your answer?
Answers
Answer:
Regulation of GFR: The kidneys have an auto regulatory mechanism for the regulation of glomerular filtration rate. It is carried out by the juxta glomerular apparatus (JGA). Juxtaglomerular apparatus is a special sensitive region formed by cellular modifications in the distal convoluted tubule and the afferent arteriole at the location of their contact. Whenever the glomerular filtration rate decreases, it activates the juxtaglomerular cells to release renin which can stimulate the glomerular blood flow and thereby brings the GFR back to normal.
The statement is wrong.
the glomerular filtration rate of a healthy individual is 180 litres per day .99 % of glomerular filtrate is reabsorbed.only 1% is secreted as urine. It is due to the tubular reabsorption .Ie,1)the reabsorption in proximal convoluted tubule .
2) reabsorption in distal convoluted tubule.
3) reabsorption in collecting duct.
# large amount of water is reabsorbed by collecting duct