文档介绍：Introductory Plant Biology
PLANT PHYSIOLOGY
二○一二年十月
主讲教师: 夏石头博士
Chapter 1 Water in Plants
Chapter Outline
Molecular Movement
Diffusion
Osmosis
Plasmolysis
Imbibition
Active Transport
Water and Its Movement through the Plant
The Cohesion-Tension Theory
Regulation of Transpiration
Transport of Food Substances (Organic Solutes) in Solution
The Pressure-Flow Hypothesis
Mineral Requirements for Growth
Macronutrients and Micronutrients
Summary
Overview
This chapter begins by introducing molecular movement through parison between balls in motion in a room and molecular activity. This is followed by a discussion of diffusion, osmosis, turgor, plasmolysis, imbibition, and active transport.
The entry of water into the plant is then explored; this is followed by a discussion of the movement of water through the plant, the evaporation of water into leaf air spaces, and transpiration. A discussion of mineral requirements for growth concludes the chapter.
Some Learning Goals
1. In simple terms, explain diffusion, osmosis, turgor, Imbibition and active transport.
2. Discuss the pressure-flow hypothesis and the cohesion-tension
3. Know the pathway, movement. and utilization of water in plants.
4. Explain how a stomatal apparatus opens and closes the pore.
5. Know and understand mineral requirements for growth.
Nearly everyone has had the experience of driving along a highway or city street when someone in the car says, "What's that smell?" Soon a bakery, or a paper mill, or perhaps a dead es into view, and the smell gets stronger. Then it fades away as the source is left behind () We take for granted the fact that there is a correlation between our proximity to an odor source and the intensity of the odor, but how and why does the odor reach us?
Diffusion
This movement of molecules or ions from a region of higher concentration to a region of lower concentration is called diffusion (Fig. ). Molecules that are moving from a region of higher