Zoology - Excretory Products and their Elimination Question with Solution | TestHub

JGA (Juxta-glomerular Apparatus): JGA works via Renin-Angiotensin mechanism which works in the following manner:
A. Fall in glomerular blood flow/glomerular blood pressure/GFR$\to$Activation of the JG cells$\to$Release of Renin in blood.
B. Angiotensinogen$\stackrel{\hspace{1em}\mathit{R}\mathit{e}\mathit{n}\mathit{i}\mathit{n}\hspace{1em}}{\to }$Angiotensin I$\stackrel{}{\to }$Angiotensin II.
C. Angiotensin II performs 2 functions:
(i) Angiotensin II is a powerful vasoconstrictor$\to$Vasoconstriction$\to$Glomerular blood pressure increases$\to$GFR increases.
(ii) Angiotensin II activates the adrenal cortex$\to$Release of Aldosterone$\to$Reabsorption of${\mathrm{N}\mathrm{a}}^{+}$and water from the distal parts of the tubule$\to$Increase in blood pressure$\to$GFR increases.