![Vascular tissues ,[object Object],[object Object],Copyright © 2010 All Rights Reserved](https://image.slidesharecdn.com/2xylemphloemtransportwatermineralsalts-101019024252-phpapp01/85/Chapter-9-Transport-in-Plants-Lesson-2-Xylem-and-Phloem-structure-and-function-1-320.jpg)
Recommandé
Contenu connexe
Tendances
Tendances (20)
Similaire à Chapter 9 Transport in Plants Lesson 2 - Xylem and Phloem structure and function
Similaire à Chapter 9 Transport in Plants Lesson 2 - Xylem and Phloem structure and function (20)
Plus de j3di79
Plus de j3di79 (20)
Dernier
Dernier (20)
Chapter 9 Transport in Plants Lesson 2 - Xylem and Phloem structure and function
- 2. Copyright © 2010 All Rights Reserved
- 4. Xylem Copyright © 2010 All Rights Reserved
- 5. Different types of lignin deposits annular rings spiral/helical bands pitted Copyright © 2010 All Rights Reserved
- 8. Sieve plates Copyright © 2010 All Rights Reserved
- 10. Structure of phloem Copyright © 2010 All Rights Reserved
- 12. Pressure flow concept Copyright © 2010 All Rights Reserved
- 16. More on aphids… Copyright © 2010 All Rights Reserved
- 17. More on aphids… Copyright © 2010 All Rights Reserved
- 19. Use of isotopes (continued…) Copyright © 2010 All Rights Reserved sunlight chlorophyll Carbon dioxide + water -> glucose + oxygen + water vapour C O 2 + H 2 O -> C 6 H 12 O 6 + O 2 + H 2 O Sunlight chlorophyll 14 C O 2 + H 2 O -> 14 C 6 H 12 O 6 + O 2 + H 2 O Sunlight chlorophyll
- 20. Use of isotopes (continued…) Copyright © 2010 All Rights Reserved
- 21. Transport of water Copyright © 2010 All Rights Reserved
- 22. Copyright © 2010 All Rights Reserved
- 23. Structure of root Copyright © 2010 All Rights Reserved
- 24. Structure of root: Zone of cell division (growing zone): actively dividing young cells (mitosis) Zone of elongation: cells elongate -> increase root length Root cap: Covers the root tip -> protects cells from injury Zone of maturation/root hairs: Region where most water + mineral salts absorbed Copyright © 2010 All Rights Reserved
- 25. Entry of water into the plant Thin film around particle = dilute solution of mineral salts Copyright © 2010 All Rights Reserved
- 26. Entry of water from soil Plasma membrane of root hair cell Osmosis Copyright © 2010 All Rights Reserved Sap in root hair Soil solution Strong solution of sugars and salts Dilute solution of mineral salts Low water potential Higher water potential H 2 O
- 27. Low water potential High water potential Copyright © 2010 All Rights Reserved
- 28. Transport of water from root hair -> xylem Copyright © 2010 All Rights Reserved
- 29. Transport of mineral salts Copyright © 2010 All Rights Reserved
- 30. Transport of mineral salts Plasma membrane of root hair cell Diffusion Copyright © 2010 All Rights Reserved Sap in root hair Soil solution Mineral concentration low Mineral concentration high Mineral salts
- 31. Why diffusion and not osmosis? Copyright © 2010 All Rights Reserved Movements are over large distances The movement is over a short distance Occurs in liquids as well as gases Occurs only in liquids It is a fast process It is a slow process No such membrane is required It requires partially permeable membrane Flow of either solute or solvent molecules is in both directions It involves flow of solvent molecules in one direction Diffusion Osmosis
- 33. High water potential Low water potential Copyright © 2010 All Rights Reserved
Notes de l'éditeur
- Transport of sugars and dissolved solutes in the phloem is kind of like water movement in the xylem in reverse. Sugars are actively pumped into the phloem sieve tube cells in the leaf. Thus the solute potential increases, making the water potential of the sieve tube cell more negative and water is drawn in from surrounding cells. In the root (and other tissues actively abstracting sugars), sugars are removed, lowering the water potential. This difference in water potential between the leaves which are actively uploading sugars, and the roots and other tissues actively removing them drives a bulk flow of water in the phloem with the sugars and other dissolved solutes. In the leaves, the concentration of sucrose in the sieve tube cells can reach as much a 1molar. This is equivalent to 10 atmospheres of pressure which can drive a bulk flow of water and sugars through the sieve tubes.