The production of urea and uric acid is because of

1. Conservation of water

2. Terrestrial adaptation

3. Terrestrial adaptation for conservation of water

4. Advancement of organism in comparison to all water animals

Kidney matrix retains some amount of urea to

1.Maintain a desired osmolarity

2.Maintain metabolism

3.Maintain balance of the body

4.Maintain micturition

Which of the following has not the protonephridia as an excretory organ?

1. Rotifers

2. Amphioxus

3. Planaria

4. Earthworm

Which of the following is not the primary function of protonephridia?

1. Ionic volume regulation

2. Fluid volume regulation

3. Osmoregulation

4. Excretion

If one goes from the outer side to the inside, which of the following parts comes first?

1. Hilum

2. Calyces

3. Pelvis

4. Cortex

Our excretory system has

1.Two million nephrons

2.One million nephrons

3.Two million neurons

4.One million neurons

For the ejection of urine the voluntary signal is given by

Micturition reflex is

How much of urea is excreted out per day?

Which of the following has no role in the elimination of excretory wastes?