The filtration units of kidneys are called:

Name any two substances which are selectively reabsorbed from the tubules of a nephron.

The volume of glomerular filtrate produced is $180 \, L$ per day,but the volume of urine excreted is just $1-2 \, L$. Give a suitable reason for this statement.

$(a)$ Name the following:
$(i)$ Part in which urine is produced.
$(ii)$ Part which stores the urine.
$(iii)$ Part which connects $(i)$ and $(ii)$.
$(iv)$ Part from which urine is passed out.
$(b)$ Name the factors on which the amount of water reabsorbed along the tubular part of the nephron depends.

Describe the process of urine formation in kidneys.

Where do the following processes take place?
$(i)$ Filtration of blood
$(ii)$ Reabsorption of glucose and water
$(iii)$ Secretion of salts to make final filtrate
$(iv)$ Collection of the final filtrate