COUNTER CURRENT MECHANISM

The increase in osmolarity from outer to inner medullary interstitium is maintained due to : (i) Close proximity between Henle's loop and vasa recta (ii) Counter current mechanism (iii) Selective secretion of HCO 3¯ and hydrogen ions in PCT (iv) Higher blood pressure in glomerular capillaries

Read the statements given below A. The renal cortex extends between the medullary pyramids as Columns of Bertini. B. ATP molecules are used in kidneys to convert NH3 to urea. C. Reabsorption of water in PCT and loop of Henle is obligatory. D. High medullary osmolarity is mainly developed due to NaCI and urea by counter current mechanism of vasa recta and loop of Henle. The correct statements are

Match column I with column II and select the correct option from the codes given below. {:("Column I","Column II"),(A." PCT",(i)." Minimum reabsorption"),(B." DCT",(ii)." Filtration of blood"),(C." Loop of Henle",(iii)." Reabsorption of 70-80% electrolytes"),(D." Counter current mechanism",(iv)." Ionic balance"),(E." Renal corpuscle",(v)." Maintenance of concentration gradient in medulla"):}

Anatomy - Reproductive System|Mechanism of Reproduction|Mechanism of Reproduction

Assertion :- Feedback mechanism for regulartion of kidney involve hypothalamus & JGA. Reason :- ANF mechanism check renin-angiotensin mechanism.

Assertion : Normal urine of man is hypertonic than the blood plasma. Reason : Counter-current mechanism of loop of Henle and Renin enzyme of juxta-glomerular cells increase the Na^(+) concentration in the adrenal medulla.

Assertion :- Human kidneys can produce urine nearly four times concentrated than the initial filtrate formed. Reason :- Counter current mechanism helps to maintain a concentration gradient in the medullary interstitium.