Stem+2

= Plant Stems!!! = ** Node ** uninsulated spaces between the "beads" of a myelin sheath where an action potential can be transmitted.
 * Internode ** the portions of the stem between the nodes
 * Bud ** undeveloped shoot of a plant
 * Vascular Bundle ** separate strands of vascular tissue within roots of plants

** Secondary Growth ** Growth in vascular plants from production of secondary tissues by a lateral meristem, usually resulting in wider branches and stems. ** Vascular cambium ** - A lateral meristem that produces secondary xylem to the inside and secondary phloem to the outside. ** Cork Cambium ** - A lateral ring of meristematic tissue found in woody seed plants, producing cork on the outside of the ring and parenchyma on the inside of the ring. Also called // phellogen. // ** Heartwood ** - The older, nonliving central wood of a tree or woody plant, usually darker and harder than the younger sapwood. Also called // duramen. // ** Sapwood ** -The newly formed outer wood located just inside the vascular cambium of a tree trunk and active in the conduction of water. Sapwood is usually lighter in color than heartwood. ** Bark ** The tough outer covering of the woody stems and roots of trees, shrubs, and other woody plants. It includes all tissues outside the vascular cambium.
 * Pith** soft spongelike central cylinder of the stems of most flowering plants
 * Primary Growth ** Growth in vascular plants resulting from the production of primary tissues by a primary meristem. Elongation of the plant body is usually a consequence of primary growth.


 * __Questions__

1. __How do the functions of a stem relate to those of the roots and leaves of a plant?__ Stems can easily relate to the roots' main function: transport. The stem's vascular tubes intercept nutrients, water, and carbohydrates that have been absorbed by the roots and transport them further throughout the plant. ** 2. __Describe how the arrangement of vascular bundles differs between monocot and dicot stems.__ In a monocot angiosperm, vascular bundles are arranged in a scattered, disorderly manner throughout the stem. In dicot angiosperms, vascular bundles are gathered in a circular ring the border the inside walls of the stem.

3. __When European settlers were struggling to clear heavily wooded land in North America, they often girdled large trees by removing a strip of bark all the way around the base of the tree. Why would this cause the tree to die?__ When the tree's lower bark is removed, the tissue that is located outside of the vascular cambium is destroyed, cutting off nutrient and water sources for the tree.