Define enzyme. Name one enzyme in humans which digests fats.

$(a)$ 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.

Explain holozoic nutrition.

$A$ few drops of iodine solution were added to rice water. The solution turned blue-black in colour. This indicates that rice water contains

Differentiate between an artery and a vein.

Which is the correct sequence of air passage during inhalation?