01:119:116 Lecture Notes - Lecture 10: Soda Straw, Ground Tissue, Phloem

• School: Rutgers University
• Department: Biological Science
• Course: 01:119:116
• Professor: Christy Beal

Document Summary

Periderm-corky outer layer; replaces older parts of the plant, typically what we think of with bark. Pith (ground tissue internal to vascular tissue) and cortex (external to vascular tissue) Cells specialized for: photosynthesis, support, short distance (cell to cell) transport. Tissue systems: dermal tissue system, ground tissue systems, vascular tissue system. Water evaporates from leaves and draws water up from roots. Stele = all vascular tissue in a plant. Two properties of h2o: cohesion: h2o sticks to itself with h-bonds. Pressure-flow hypothesis phloem (high pressure) and sink where sugar is removed from phloem (low p) Pressure gradient exists between source where sugar is loaded into: adhesion: h2o sticks to other things with h-bonds. Allows unbroken water column to form and adhere to xylem walls; there are ledges and valves that allow water storage and cells that allow it to be reformed/reestablished. Answer: plasmodesma: provide a path connecting the cytoplasm of one cell to another.