Differentiate between primary and secondary growth in plants. Be sure to include the results of each and where each type of growth would be most likely to occur.

Primary growth refers to growth in stem and root length. This vertical growth occurs only at the root and shoot tips, specifically at the root and shoot apical meristems. Primary growth results in the formation of primary tissues, such as primary xylem, primary phloem, parenchyma, collenchyma, and sclerenchyma. Secondary growth refers to lateral growth; that is, secondary growth results in an increase in the girth of the plant. Secondary growth results from the activity of lateral meristems, which in term produce secondary tissues; the vascular cambium produces secondary xylem and secondary phloem, and the cork cambium produces cork parenchyma and cork cells. These last three tissues comprise the periderm, which replaces the epidermis in woody plants.