What is stem ? Describe parts of stem and normal functions.

$\rightarrow$ The stem is the ascending part of the axis bearing branches, leaves, flowers and fruits. It develops from the plumule of the embryo of a germinating seed. They bear nodes and internodes.

$\rightarrow$ The region of the stem where leaves are born is called node while internodes are the portions between two nodes. The stem bears buds, which may be terminal or axillary.

$\rightarrow$ Stem is generally green when young and later often become woody and dark brown.

$\rightarrow$ Main functions of the stem :

$(i) $ Spreading out branches bearing leaves, flowers and fruits.

$ (ii)$  It conducts water, minerals and photosynthates.

$ (iii)$  Some stems perform the function of storage of food, support, protection and of vegetative propagation.