The juxtaglomerular apparatus
A)secretes renin in response to sodium depletion in the filtrate
B)is a thickened region of specialized cells at a point where the distal tubule comes into intimate contact with the afferent and efferent arterioles of the same nephron
C)secretes renin in response to a drop in afferent arteriole blood pressure
D)secretes renin in response to sympathetic impulses
E)has all of the above characteristics

Question

Quizplus · Accepted Answer

The juxtaglomerular apparatus has all of the above characteristics. It is a specialized structure consisting of a group of cells in the walls of the afferent arteriole where it comes into contact with the distal convoluted tubule. These cells sense changes in the blood pressure and sodium levels in the distal tubule and secrete renin, which initiates the renin-angiotensin-aldosterone system to regulate blood pressure and electrolyte balance. The secretion of renin can be stimulated by sodium depletion in the filtrate, a drop in afferent arteriole blood pressure or sympathetic impulses.

The Juxtaglomerular Apparatus