Which of the following process of urine formation takes place all along the renal tubule and collecting duct?

1. Ultrafiltration and tubular reabsorption

2. Ultrafiltration and tubular secretion

3. Tubular reabsorption and secretion

4. Anti-current mechanism and reabsorption

In man, in which part of the uriniferous tubule reabsorpton of glucose occurs?
(1) Collecting tube

(2) Henle's loop

(3) Distal convoluted tubule

(4) Proximal convoluted tubule

Which part of the nephrons is impermeable to water?
1. Proximal convoluted tubule
2. Distal convoluted tubule
3. Ascending limb of loop of Henle
4. Descending limb of loop of Henle

When kidney of a person is damaged, he/she invariably suffers fom anaemia because

(1) RBCs pass through the glomerulus

(2) Sufficient erythropoietin is not produced

(3) haemoglobin is not synthesised sufficiently

(4) Iron and viatmin B-12 are not able to bind to haemoglobin.

What is true of urea biosynthesis?

(1) Uric acid is starting point

(2) Urea is synthesised in lysosomes

(3) Urea cycle enzymes are located inside mitochondria

(4) Urea is synthesised in kidney

Refer the given figure of nephron.

Identify A, B, C and D and select the correct option regarding them
1. A- Glomerulus-a tuft of capillaries formed by afferent arteriole.
2. B-PCT-reabsorption of ${\mathrm{HCO}}_3^{-}$ and selective secretion of H⁺ and K⁺ occurs here.
3. C-DCT-almost all glucose, amino acids, water, Na⁺, K⁺ and uric acid are absorbed here.
4. D-collecting duct-extends from the cortex of the kidney to the inner parts of medulla. Large amount of water is secreted in this region.

Which of the following is true for excretion in humans?

1. Glucose and amino acids are reabsorbed in PCT by simple diffusion.

2. DCT is permeable to water.

3. On average, 25-30 gm of urea is excreted out per day.

4. Maximum reabsorption occurs in the loop of Henle.

Which one of the following is correct regarding the excretion?

1. Large amount of water from renal filtrate is reabsorbed in DCT and a less amount is reabsorbed by PCT.

2. The descending limb of loop of Henle is completely impermeable to salts.

3. Malpighian corpuscle is found in medulla region of kidney

4. The colour of urine is pale yellow and is slightly alkaline in nature.

Which one of the following statements is correct with respect to salt water balance inside the body of living organisms?
(1) When water is not available camels do not produce urine but store urea in tissues.

(2) Salmon fish excretes lot of stored salt through gill membrane when in fresh water.

(3) Paramecium discharges concentrated salt solution by contractile vacuoles.

(4) The body fluids of fresh water animals are  generally hypotonic to surrounding water.

A person passes much urine and drinks much water but his blood glucose level is normal.

This condition may be the result of:

1. A reduction in insulin secretion from pancreas

2. A reduction in vasopressin secretion from posterior pituitary.

3. A fall in the glucose concentration in urine

4. An increase in secretion of glucagon