Secondary Growth in Plants: A Study Guide - Prof. Thomas Elthon, Study notes of Biology

Download Secondary Growth in Plants: A Study Guide - Prof. Thomas Elthon and more Study notes Biology in PDF only on Docsity! Study Guide - Secondary Growth in Plants 2011 During secondary growth, what happens to the pith and primary xylem? (2) The pith and primary xylem become covered with secondary xylem and remain in their original position What happens to the primary phloem, the cortex, and epidermis during initial secondary growth? (3) 1. The primary phloem is pushed outward, is fragmented, and becomes non-conducting. 2. The cortex and epidermis can persist for many years, the epidermis does so through cell division. What is periderm? (3) The periderm is the cork cambium and it’s derivatives, parenchyma cells produced to the inside and cork cells to the outside The vascular cambium has two types of initials. List these and indicate what each produces. (4) 1. Fusiform Initials: produce xylem to the inside and phloem to the outside 2. Pay Initials: produce parenchyma cells to the inside and to the outside What functions do vascular rays perform? (2) 1. Radial movement of materials in the stem 2. Storage In stems, the initial cork cambium forms from parenchyma cells in the outer region of the cortex. Explain how successive cork cambia form. (2) Form from parenchyma cells formed by the last cork cambium or by parenchyma cells in the phloem Bark is defined as everything outside of the vascular cambium. (2) Give 2 defining characteristics of cork cells. (2) 1. Dead at maturity 2. Have suberized cell walls to prevent water loss List 4 characteristics of cork that makes it beneficial to the plant. (4) 1. Impervious to water 2. Thermal insulator 3. Compressible and resilent 4. Light in weight Stems have lenticels to allow for air penetration into the phloem and vascular cambium regions. (2)