Different types of stems
(a) Monocots. Secure stems of various plants such as bamboo, sugar cane and corn. Cut every of the stems crosswise with a very sharp knife or razor blade. Observe the similarities in the cut cross sections. Especially notice that the tubes or fibro-vascular bundles are scattered throughout the pith on the under of the stem.
(b) Dicers. Secure the stems of various plants or small trees like as willow, geranium, tomato, etc. Cut across every of these stems with a sharp knife or razor blade. Observe that just under the outside layer of the stem there is a bright green layer. This is the cambium layer. Also observe that the tubes or fibro- vascular bundles are arranged in a ring about the central or woody portion of the stem.