BIOL 2304 Study Guide - Quiz Guide: Xylem, Repressor, Gibberellin
Document Summary
Quiz 6 questions will be based on material from lectures 12, 13 and 14 and the two short presentations on plants as sources of biofuels and drugs. Auxin suppresses bud outgrowth and promotes apical dominance. Cytokinins promote shoot branching: the role of gibberellin in stem elongation. Be able to correlate particular gene mutations with gibberellin related phenotypes (dwarf, hyperelongation). Ga promotes growth through cell expansion and division. Dwarf- ga3 oxidase produces active ga. loss of function reduces active. Ga binds to gid1, and this ga/gid1 complex binds to della, which is then degraded. Pay attention to the cross section of a stem with secondary growth and the position of the different tissues. Secondary phloem and secondary xylem come from vascular cambium. Inner bark is secondary phloem, outer bark is outside cork cambium: function of lenticels in the bark. Early wood is less dense, wider cells and thinner walls, than late wood.
