A stem is distinguished from the root by the following character

A stem is negatively geotropic, green in younger stages, positively phototropic, has nodes and internodes, has axillary buds and terminal buds, possessing leaves, flowers, fruits, not having a protective cap like structure, has appendages of exogenous origin only, able to form adventitious roots, having multicellular trichomes and stomata, develops from plumule, having cuticle over its surface etc.