Question

A large quantity of fluid is filtered everyday by nephrons in the kidneys but only about 1% of it is excreted as urine. The remaining 99% of the filtrate
A) Is stored in the urinary bladder
B) Is reabsorbed into the blood
C) Gets collected in the renal pelvis
D) Is lost as sweat

Answer 1

Hint: Nephron regulates the amount of water and soluble substance in the blood by filtering, reabsorbing and excreting. Reabsorption of water and minerals takes place at the tubules and the collecting duct.

Complete Answer:
- Nephron is the structural and functional unit of the kidney.
- The large amount of fluid first passes through the glomerulus where ultrafiltration takes place. Then the reabsorption of minerals takes place in the proximal convoluted tubule.
- Glucose, water and amino acids are reabsorbed in this part. In the loop of Henle further urine is concentrated.
- When the remaining filtrate enters the distal convoluted tubule, potassium and sodium are reabsorbed.
- The water is largely reabsorbed in the collecting duct. Thus the urine formed is very concentrated as the rest of the water and minerals are reabsorbed to the blood.

- In the urinary bladder, the residual urine is stored which has been filtered by the nephron.
- The renal pelvis acts as funnel for urine flowing to the ureter.
- Sweat is produced by the sweat glands in the skin.

The correct answer is B. The water is reabsorbed in the blood.

Note: The majority of the water is reabsorbed in the nephron. Most of the water in the glomerular filtrate is reabsorbed by the tubules and collecting duct. The residual water along with the mineral waste is eliminated by our body as urine.