1. Plant Structures Roots, Stems, and Leaves
Chapter 23

2. Plants Roots Stems Leaves Seed plants have three main structures:
Linked together by various means

3. Function of Roots Roots Absorb/Transport water and nutrients
Anchor plant to the ground
Hold soil in place and prevent erosion
Storage of sugars made
In photosynthesis

4. Functions of Stems Stems Support for the plant body
Carries nutrients throughout plant

5. Functions of Leaves Leaves Main photosynthetic systems
Sight of gas exchange

6. Tissues in Plants
Dermal tissue
Vascular tissue
Ground tissue

7. Tissues in Plants 1. Dermal Tissue Cuticle Outer covering
– waxy coating
Roots have dermal tissue
Root hairs
Stomata and Guard cells within

8. Tissues in Plants 2. Vascular Tissue Xylem Phloem Transport System
V for vascular, V for vein!
2. Vascular Tissue
Transport System
Carries water and
nutrients.
Xylem
(Water in)
Phloem
(Glucose out)

9. Tissues in Plants 3. Ground Tissue
Cells between dermal and vascular tissue

10. Taproots Fibrous roots *Roots Types of Roots Long, thick root
Reach deep into the soil to obtain water/nutrients
Fibrous roots
Many thin roots
Spread out away from plants to find water and nutrients quickly
Helps to reduce erosion of soil
Taproot
Fibrous root

11. Roots Anchor plant Absorb water/nutrients Storage of sugar
Root Functions
Anchor plant
Absorb water/nutrients
Storage of sugar

12. Stems Functions Produce leaves, branches, and flowers Hold leaves up
Transport substance between roots and leaves

13. Stems
2 types of stems
Herbaceous
Woody

14. Stems Xylem and phloem Transport water and nutrients Contain nodes
– attachment for leaves

15. Leaves Function Photosynthesis Covered by: epidermis and cuticle
Main site of:
Photosynthesis
Covered by:
epidermis and cuticle
Create water proof barrier

16. Leaves 1. Palisade mesophyll 2. Spongy mesophyll -some photosynthesis
Mesophyll (meso=middle)
1. Palisade mesophyll
-site of most photosynthesis
2. Spongy mesophyll -some photosynthesis

17. Leaves Stomata Guard Cells – Surround the stomata Gas exchange CO2 in
– pores in the underside of the leaf
Gas exchange
CO2 in
O2 out
Guard Cells – Surround the stomata
Open and closes stomata
***Stomata closed at night to prevent H2O loss

18. Transpiration Leaves Loss of water through its leaves
Replaced by water drawn into the leaf

19. Transport in Leaves Xylem Phloem Vein (Vascular Tissue)
“Water in” for photosynthesis
Phloem
“Glucose out” after photosynthesis

20. Tropisms Growing toward or away from a stimulus
Phototropism Stimulus = Light Leaves have positive phototropism
Thigmotropism
Stimulus = Touch
Vines have positive thigmotropism

21. Tropisms Growing toward or away from a stimulus
Gravitropism Stimulus = Gravity Roots have positive gravitropism
Hydrotropism
Stimulus = Water
Roots have positive hydrotropism

23. Plant Adaptations

24. Types of Adaptations
Structural adaptations are the way something is built or made.
Behavioral adaptations are the way something acts naturally or by instinct.

25. Behavioral Adaptations
Adaptations to get food
Plants like the Venus fly trap, trap insects for food.

26. Behavioral Adaptations
Adaptations for reproduction
Plants drop seeds to grow new offspring.

27. Structural Adaptations
Adaptations to get water and nutrients
Roots soak up water and nutrients from soil.

28. Structural Adaptations
Adaptations for defense
Spines and thorns protect plants from predators

29. Structural Adaptations
Adaptations for defense
Poison Ivy and Poison oak have toxins that give predators a painful itchy rash.

30. Desert Adaptations
Small leaves or spines on desert plants conserve water.
Thick waxy skin holds in water.
Roots near the soils surface soak up rain water quickly before it evaporates.

31. Rainforest Adaptations
Smooth, slippery bark keeps vines from killing trees.
Slide shaped leaves lets rain run off so fungus doesn’t grow on plants.