Lesson 2 of 13 · 6 min
The stem
NCERT §5.2
Nithya finds a sprouting potato in the kitchen basket. It grew underground, yet it has little 'eyes' with buds in them. Is it a root or a stem?
The lesson in notes
In short
The stem is the part of the plant axis that grows upward. It carries branches, leaves, flowers and fruits, and it grows from the plumule of the embryo when the seed germinates.
Nodes are the points where leaves arise; internodes are the lengths of stem between two neighbouring nodes.
The stem carries buds, which are either terminal (at the tip) or axillary (in the angle between a leaf and the stem).
A young stem is usually green; later it often becomes woody and dark brown.
Its main work is to spread out the branches that hold leaves, flowers and fruits, and to conduct water, minerals and photosynthates.
Some stems also store food, give support or protection, or reproduce the plant vegetatively.
How to tell a stem from a root: nodes and internodes, multicellular hairs, and growth towards light (the stem is positively phototropic).