1. Plant Structures Roots, Stems, and Leaves

2. Specialized Tissues in Plants
Plants are as successful if not more successful than animals
Seed plants have three main structures:
Roots
Stems
Leaves
Linked together by various means

3. Roots Absorb water and nutrients Anchor plant to the ground
Hold soil in place and prevent erosion
Protect from soil bacteria
Transport water and nutrients
Provide upright support

4. Roots Plant Nutrient Uptake Plant requirements
Soil type determines plant type
Plant requirements
Oxygen, CO2
Nitrogen
Phosphorus
Potassium
Magnesium
Calcium
Trace elements

5. Root Hairs Root hairs use energy to: Pump minerals from the soil
Causes water molecules to follow by osmosis (movement of water)

6. Stems Support for the plant body Carries nutrients throughout plant
Defense system to protect against predators and infection
Few millimeters to 100 meters

7. Stems Stem Structure Essential part of transport system
Produce leaves, branches, and flowers
Hold leaves up
Transport substance between roots and leaves
Essential part of transport system
Function in storage and photosynthesis

8. Stems Xylem and phloem – major tubule systems
Transport water and nutrients
Contain nodes – attachment for leaves
Internodes – regions between the nodes
Buds – undeveloped tissue
Petiole – attaches the leaf to the stem

9. Stems – Vascular Tissue
Transport System
Subsystems
Xylem
Phloem
Subsystems are used to carry fluids and organic materials throughout plant

10. Stem – Xylem and Phloem

11. Stem - Phloem
Organic materials are transported up and down the plant in the phloem
This is called translocation
The two main substances transported are nitrogen based substances and carbohydrates, such as glucose

12. Stem - Xylem
The transport of water up from the roots of the plant is through the xylem.
This is called the transpiration stream and occurs through the stomata.
The loss of water vapour from the leaves through the stomata is called transpiration

13. Stem - Transport in Plants
Transpiration and Wilting
Water pressure – keeps plants semi-rigid
Wilting is a result of high transpiration rates
Loss of water causes a drop in water pressure
Loss of rigidity
Conserves water

14. Leaves Leaves Main photosynthetic systems
Susceptible to extreme drying
Site of oxygen/carbon dioxide intake and release

15. Leaves Main site of photosynthesis Consist of:
Blade – thin flattened section
Petiole – stalk that attaches stem to blade
Covered by epidermis and cuticle
Create water proof barrier

16. Microscopic Leaf Structure

17. Leaves Stomata – pores in the underside of the leaf
Guard Cells – Surround the stomata
Stomata is controlled by water pressure in guard cells

18. Leaves - Stomata Controlling Transpiration
Open the stomata – increase water loss
Close the stomata – decrease water loss

19. Leaves Gas Exchange Take in CO2 and release O2
Gas exchange also takes place at the stomata
Not open all the time

20. Leaves - Chloroplasts Chloroplasts are found in leaf cells
They contain a green pigment called chlorophyll
Chlorophyll absorbs light energy – which is essential for photosynthesis