ROOTS
Raven 7th, p. 528-541; 8th, p. 558-578
Introduction
Both young roots and mature roots have specific functions. These functions include absorption, anchorage, and food storage. As you examine roots keep these functions in mind, and look for associated structural modifications. A root is forced through the soil as it grows, and must thus cope with the abrasiveness of the soil particles. How does it cope?
Roots have three tissues (rootcap, endodermis, and pericycle) which are not usually present in stems of gymnosperms (conifers) and angiosperms (flowering plants). The arrangement of vascular and meristematic tissues also differs. As you can see in this picture roots have a protostele. How does this differ from stems. Branches do not arise from nodes in roots.