1. Transport in Angiospermatophyta

2. Outline of IS Leaf (tissue)

3. Outline of IS of stem (tissue)

4. Outline of IS Root (tissue)

5. Root system provide large surface area

6. Branching and Root hairs
The cells with hairs have a greater cell wall size
To absorb-
Mineral ion
Water
Structure of cortex –facilitates water uptake

7. Plants absorb their nutrients in inorganic form
N as Nitrate, Ammonium ion
K as potassium ion
P as Phosphate ion
Ca as Calcium ion.

8. Three main methods for the absorption
Diffusion
Via fungal hyphae
Mass flow

9. Diffusion
Some minerals are more concentrated in the soil than in the root and when dissolved in water will diffuse into the root

10. Fungal hyphae Fungus help many plant species to absorb minerals.
The thread of fungus grow thru the soil and absorb M
Some grow into the plant roots and transport these M in the root
Fungus receives sugars from the plant
Ex. Mutualism.

11. Ex., Oak, Beech and Birch all form ectomycorrhizal relationships with a number of fungi.

12. Ectomycorrhiza

13. In ectomycorrhizae
The mycelium of the fungus forms a dense sheath over the surface of the root

14. In endomycorrhizae Microscopic fungal hyphae extend into roots
Endomycorrhizae. No mantle forms around the root. Within the root cortex, the fungus makes extensive contact with the plant through branching of hyphae
providing an enormous surface area for nutrient swapping

15. Agricultural Importance of Mycorrhizae
Farmers and foresters
Often inoculate seeds with spores of mycorrhizal fungi to promote the formation of mycorrhizae

16. Mass flow of water.
The plant takes large volume of water which contains some dissolved minerals.
Minerals dissolved in water form hydrogen bonds with water such that the movement of water towards the root 'drags' the minerals with the water.

17. Active transport
plants can take up K+ from the soil against a ten-thousand-fold concentration gradient
e.g., from as little as 10 µM in the soil to 100 mM in the cell.

18. Terrestrial plant Support themselves— - thickened cellulose
- cell turgor
-lignified Xylem

21. Water and minerals can travel through a plant by one of three routes
Out of one cell, across a cell wall, and into another cell
Via the symplast
Along the apoplast

22. Water and minerals ascend from roots to shoots through the xylem
Plants lose an enormous amount of water through transpiration, the loss of water vapor from leaves and other aerial parts of the plant
The transpired water must be replaced by water transported up from the roots

23. Xylem sap
Rises to heights of more than 100 m in the tallest plants

24. Pushing Xylem Sap: Root Pressure
At night, when transpiration is very low
Root cells continue pumping mineral ions into the xylem of the vascular cylinder, lowering the water potential
Water flows in from the root cortex
Generating root pressure

25. Pulling Xylem Sap: The Transpiration-Cohesion-Tension Mechanism
Water is pulled upward by negative pressure in the xylem

26. Transpirational Pull Water vapor in the airspaces of a leaf
Diffuses down its water potential gradient and exits the leaf via stomata
Transpiration produces negative pressure (tension) in the leaf
Which exerts a pulling force on water in the xylem, pulling water into the leaf

27. Cohesion and Adhesion in the Ascent of Xylem Sap
The transpirational pull on xylem sap
Is transmitted all the way from the leaves to the root tips and even into the soil solution
Is facilitated by cohesion and adhesion

29. The movement of xylem sap against gravity
Is maintained by the transpiration-cohesion-tension mechanism
Stomata help regulate the rate of transpiration
Leaves generally have broad surface areas
And high surface-to-volume ratios

30. Both of these characteristics
20 µm
Figure 36.14
Both of these characteristics
Increase photosynthesis
Increase water loss through stomata

31. Plants lose a large amount of water by transpiration
If the lost water is not replaced by absorption through the roots
The plant will lose water and wilt

32. Transpiration also results in evaporative cooling
Which can lower the temperature of a leaf and prevent the denaturation of various enzymes involved in photosynthesis and other metabolic processes
About 90% of the water a plant loses
Escapes through stomata

33. Each stoma is flanked by guard cells Which control the diameter of the stoma by changing shape Changes in turgor pressure that open and close stomata

34. animation

35. Abiotic Factors affect the rate of Trpn.
Light
Temperature
Wind
Humidity

36. Xerophyte Adaptations That Reduce Transpiration
Xerophytes
Are plants adapted to arid climates
Have various leaf modifications that reduce the rate of transpiration
The stomata of xerophytes
Are concentrated on the lower leaf surface
Are often located in depressions that shelter the pores from the dry wind