Countercurrent Mechanism

Q. Henle’s loop along with _________ play a significant role in __________ which helps to produce concentrated urine.

1. glomerulus; ultrafiltration
2. glomerulus; counter current mechanism
3. vasa recta; counter current mechanism
4. vasa recta; secretion

Q. Counter current mechanism helps in concentrating urine in animals and mainly operates on:
a. Henle's loop b. Vasa-recta
c. PCT d. DCT

1. a only
2. b only
3. a and b
4. All of these

Q.

Give a brief account of the counter current mechanism.

Q. Which of the following statements is/are correct?
I. Urine is hypertonic in distal convoluted tubule.
II. When the urine pases into the collecting tubule, it becomes hypotonic.
III. Urine is isotonic in Proximal Convoluted Tubule (PCT).
IV. Urine becomes more and more hypotonic as it passes throught the Henle's loop.
Select the correct answer using the codes given below.

1. Only I
2. Only III
3. I and IV
4. I, II and III
5. II and III

Q. The gradient in the counter current mechanism is mainly caused by NaCl and urea.

1. False
2. True

Q.

Indicate whether the following statements are true or false:
ADH helps in water elimination, making the urine hypotonic.

Q. Counter current mechanism helps in ________ osmolarity towards the inner medulla.

1. constant
2. increasing and then decreasing
3. decreasing
4. increasing

Q. Deficiency of vasopressin primarily results in:

1. Increased volume of urine
2. Decreased volume of urine
3. Excessive secretion of urochrome
4. Change in pH from acidic to alkaline range

Q. Henle’s loop along with _________ play a significant role in __________ which helps to produce concentrated urine.

1. glomerulus; ultrafiltration
2. glomerulus; counter current mechanism
3. vasa recta; counter current mechanism
4. vasa recta; secretion

Q.

How is the amount of urine produced in humans is regulated?

Q.

Which structures are primarily involved in the countercurrent mechanism?

Q.

What are the two faults in a potentiometer if the balance point is not obtained?

Q.

Where does passive transport occur in the body?

Q.

The kidneys resemble the contractile vacuoles of amoeba in:

1. expelling out glucose

2. expelling out urea and uric acid

3. expelling out excess of water

4. expelling out salts

Q. Compared to human blood, human urine is

1. hypotonic
2. isotonic
3. hypertonic
4. All of the above

Q. Which feature enables the mammalian kidney to concentrate urine in the medullary region ?

1. Maintaining a high osmotic pressure in the tissues between the tubules.

2. Rapid flow of blood through the medulla
3. Rapid removal of sodium ions from medullary tissue.
4. High oxidative metabolism of medullary cells

Q.

Explain the machanism of formatioin of concentrated urine in mammals.

Q.

Read the assertion and reason carefully to mark the correct option in question.

Assertion: The two limbs of Henle’s loop form a counter current.

Reason: The flow of blood in the two limbs of Henle’s loop is in opposite direction.

1. If both assertion and reason are true but the reason is not the correct explanation of the assertion.

2. If both assertion and reason are false.

3. If both assertion and reason are true and the reason is the correct explanation of the assertion

4. If assertion is true but the reason is false.

Q. Counter current mechanism helps in concentrating urine in animals and mainly operates on:
a. Henle's loop b. Vasa-recta
c. PCT d. DCT

1. a only
2. b only
3. a and b
4. All of these

Q.

What Are Complex Numbers Used For

Q. Reabsorption in tubules of nephrons occurs by

1. Osmosis
2. Active transport
3. Diffusion
4. Both B and C

Q.

The three interrelated processes of urine formation are -

1. Filtration, secretion and excretion

2. Secretion, reabsorption and micturition

3. Excretion, storage and micturition

4. Filtration, reabsorption and secretion

Q.

Part of nephron impermeable to salt is

1. PCT

2. Descending limb of Henle’s loop

3. Ascending limb of Henle’s loop

4. DCT

Q. Which of the following factors is responsible for the formation of concentrated urine?

1. Hydrostatic pressure during glomerular filtration
2. Low levels of antidiuretic hormone
3. Maintaining hyperosmolarity towards the medullary interstitium in the kidneys
4. Secretion of erythropoietin by juxtaglomerular complex

Q. mechanism is responsible for production of concentrated urine.

1. Co-current
2. Counter currrent
3. Reabsorption
4. Secretion

Q. Which of the following statements is/are false?

(I) Urine is hypertonic in distal convoluted tubule.
(II) When urine passes into the collecting tubule, it becomes hypotonic.
III) Urine is isotonic in proximal convoluted tubule.
(IV) Urine becomes more and more hypotonic as it passes down the Henle’s loop.

1. I and IV
2. I, II and III
3. II and III
4. I only

Q. Vasopressin released from the neurohypophysis is mainly responsible for

1. Facultative reabsorption of water through Henle's loop
2. Obligatory reabsorption of water through PCT
3. Facultative reabsorption of water through DCT
4. Obligatory reabsorption of water through Bowman's capsule

Q.

The emitter of the transistor should be?

Q. Fill in the blanks with appropriate words.
The hormone ADH increases the absorption of.......... from the collecting duct.

Q. Henle’s loop along with _________ play a significant role in __________ which helps to produce concentrated urine.

1. vasa recta; counter current mechanism
2. glomerulus; ultrafiltration
3. glomerulus; counter current mechanism
4. vasa recta; secretion