Juxtaglomerular apparatus (JGA) is formed by modifying the distal convoluted tubule and afferent arteriole. It is located where the afferent arteriole and the distal convoluted tubule (DLT) come in contact. It contains juxtaglomerular cells which are the specialized cells of the arteriole and also contain an enzyme that regulates blood pressure and this enzyme is called renin. Fall in glomerular filtration rate activates the juxtaglomerular cell which causes the release of renin. Renin stimulates the glomerular blood flow by which the glomerular filtration rate comes to normal. Angiotensin gets converted into Angiotensin I with the help of renin and further conversion into Angiotensin II takes place. Angiotensin II increases the glomerular filtration rate by an increase in glomerular blood pressure. It also releases aldosterone by activating the adrenal cortex. The mechanism of renin and angiotensin is known as the Renin-Angiotensin mechanism.
Answered by Abhisek | 1 year ago
Fill in the gaps:
(a) Ascending limb of Henle’s loop is ______ to water whereas the descending limb is _______ to it.
(b) Reabsorption of water from distal parts of the tubules is facilitated by hormone _______.
(c) Dialysis fluid contain all the constituents as in plasma except _______.
(d) A healthy adult human excretes (on an average) _______ gm of urea/day
Name the following:
1. A chordate animal having flame cells as excretory structures.
2. Cortical portions projecting between the medullary pyramids in the human kidney.
3. A loop of capillary running parallel to Henle’s loop.
Terrestrial animals are generally either ureotelic or uricotelic, not ammonotelic, why?
What is meant by the term osmoregulation?
Match the items of Column I with those of column II:
|Column I||Column II|
|(a) Ammonotelism||(i) Birds|
|(b) Bowman’s capsule||(ii) Water reabsorption|
|(c) Micturition||(iii) Bony fish|
|(d) Uricotelism||(iv) Urinary bladder|
|(e) ADH||(v) Renal tubule|