2. titletitle

3. Transport in flowering plants is provided by vascular tissue xylemphloem transport water substances dissolved in water transport organic nutrients

4. Distribution of vascular tissue in dicotyledonous plant leaf leaf vein midrib vein xylem phloem

5. Distribution of vascular tissue in dicotyledonous plant xylem phloem stem cortex Vascular bundle

6. root Distribution of vascular tissue in dicotyledonous plant xylem phloem cortex

7. Xylem cells xylem vessels xylem tissue is made up of xylem vessels dead, hollow cells thick cellulose cell walls with lignin no cross wall between cells provide support to plant other than transport

8. phloem cells Phloem cells phloem tissue is made up of sieve tubes and companion cells living cylindrical cells (cytoplasm,no nucleus) thin cellulose cell walls with no lignin joining end to end to form long tube substances can pass from cell to cell through sieve plates 1. sieve tubes sieve tube

9. phloem cells Phloem cells phloem tissue made up of sieve tubes and companion cells narrow cell with a nucleus / numerous organelles support the metabolic activities of the sieve tubes 2. companion cells companion cell

10. The plant wilts Turgidity of cells provides support to plants The cells of leaves lack water

11. Osmosis in plant cells In a solution with higher water potential –water moves in by osmosis –cell turgid  fully turgid In a solution with lower water potential –water moves out by osmosis –cell flaccid  plasmolyzed

12. evaporation transpiration absorption by root Water Balance in plant lose water gain water

13. Transpiration in plants What is transpiration? loss of water vapour from surfaces of plants due to evaporation

14. Where does transpiration occur? stomata ( > 90% ) lenticels ( < 10%) waxy cuticle (very small amount)

15. water lost from leaves Transpiration through stomata consists of 2 steps : 1Water evaporates into the air space 2Water diffuses out through the stoma

16. water lost from leaves Water is replaced by : 1Water is lost from the cell surface (cell wall), 2As a result, cells draw water from the xylem, pulling water up the plant. which is replaced by the water in the cell. Each cell then pulls water from its neighbouring cells. through cell wall through cytoplasm and vacuoles

17. Light intensity –more CO 2 for photosynthesis  light intensity  more water vapour diffuses out  stomata  transpiration rate  open more widely transpiration rate light intensity  SA for diffusion of water vapour   light intensity   Temperature

18. Temperature   temperature  more water vapour diffuses out  rate of evaporation  transpiration rate   rate of diffusion of water vapour  temperature ( o C) transpiration rate 30251520  diffusion gradient 

19.   diffusion gradient of water vapour  concentration of water vapour in the surrounding air more  water diffuses out Relative humidity relative humidity  lower  relative humidity of atmosphere (%) transpiration rate 020406080100  transpiration rate

20.  remove water vapour accumulating near the leaf surface  diffusion gradient of water vapour  Air movement   more air movement  water vapour diffuses out  transpiration rate   more   rate of diffusion  wind velocity (km/h) (air movement) transpiration rate 081624

21. To Measure the Rate of Transpiration by Using a Simple Potometer

22. What are the environmental conditions under which transpiration occurs quickly ? Ans: It is under dry, warm and windy conditions. air/water meniscus graduated capillary tube reservoir leafy shoot tap

23. Ans: No. It is because it only measures the rate of water uptake by the leafy shoot … Ans: In addition, it is too small to fit the whole root system and this may affect the rate of water uptake. Does this apparatus give you an accurate measurement of the rate of transpiration ? air/water meniscus graduated capillary tube reservoir leafy shoot tap

24. Sometimes you may introduce an air bubble into the capillary tube. State the advantage of this method. Ans: Movement of the air bubble is easier to observe than that of air/water meniscus. air/water meniscus graduated capillary tube reservoir leafy shoot tap

25. Sometimes you may introduce an air bubble into the capillary tube. State the disadvantage of this method. Ans: Friction between the capillary wall and the bubble may affect the movement of bubble. air/water meniscus graduated capillary tube reservoir leafy shoot tap

26. To Measure the rate of water uptake and water loss of a plant using a weight potometer

27. Change in volume in burette Change in weight of the whole set-up = (V2 – V1)cm 3 = (W1 – W2)g = amount of water uptake = amount of water loss V2 V1 W1 W2 24 hours

28. = (V2 – V1) / 24 cm 3 /hr = (W1 – W2) / 24 g/hr Rate of water uptake Rate of water loss V2 V1 W1 W2 24 hours Rate of water loss > Rate of water uptake Water retained Photosynthesis / new cells 1cm 3 water = 1g water

29. in flowering plants provided by Transport consist of carriescarries Concept diagram vascular tissues xylem phloem water organic nutrients

30. Transport of water and mineral salts Xylem vessels transport –water –mineral salts by transpiration pull water forms a continuous stream inside water drawn out of xylem vessels to replace water loss through leaf transpiration water in xylem vessels is moved up as plants transpire minerals and other substances dissolved in water can be transported up the plant

31. water and minerals absorbed by roots bud Transport of organic nutrients Phloem transport - organic nutrients by translocation through sieve plates moving up to growing part moving down to growing fruit and root for storage organic nutrients made by photo- synthesis