1. Plants

2. Classification Timeline
500 million years ago: Algae
Example: Blue-green algae
425 million years ago: Land plants (bryophytes)
Example: Mosses
375 million years ago: Vascular seedless plants (pterophytes)
Example: Ferns
200 million years ago: Vascular seeded plants (gymnosperms)
Example: Pine Trees
130 million years ago: Flowering plants (angiosperms)
Example: Daffodils

3. Non-vascular plants: Algae
Non-vascular- no tubes to transport water & nutrients or provide support
All movement occurs through osmosis
Aquatic
Can photosynthesize- use sunlight to produce its own energy
Essential source of oxygen in aquatic ecosystems (70-80% oxygen comes from algae)

4. Non-vascular plants: Bryophytes
Bryophytes- non-vascular plants
No tubes to transport water & nutrients or provide support to the plant
All movement occurs through osmosis
No true stems, leaves, or roots
Rhizoids act as roots- absorb water & minerals
Need water to reproduce
Less likely to survive harsh conditions because of need for water

5. Vascular Plants: Pterophytes, Gymnosperms, & Angiosperms
Contain vascular tissue
Xylem & Phloem
Xylem transports water
Phloem transports sugars
Pterophyte
Gymnosperm
Angiosperm

6. Angiosperm Classification: Monocot vs. Dicot

7. Angiosperm Classification: Alternate vs. Opposite Leaves

8. Roots Purpose Increase surface area to absorb more water & minerals
Anchor plant
Store water & minerals

9. Types of Roots Tap- one main root that goes straight down
I.e. Carrot
Fibrous- has root hairs or lateral roots
Aerial- roots exposed to air
aerial

10. Parts of the Root
Cross section
Root hair- increase surface area to absorb more water & minerals
Epidermis- protection & absorption
Cortex- Movement of water & minerals to center of root
Storage of food
Endodermis- assists in movement of water & minerals to center of root
Xylem- movement of water
Phloem- deliver food to root
Apical meristem- area of growth
Root cap- protection & helps root elongate farther into soil
Longitudinal

11. Herbaceous Stem Contains vascular bundles
Monocot- vascular bundles spread
throughout
Contains vascular bundles
Xylem & phloem
Xylem (inside of vascular bundle)
Dead cells
Main purpose to move water through the stem
Phloem (outside of vascular bundle)
Alive at maturity
Main purpose to move sugars down through stem
Cortex
Water & minerals transported
Epidermis
Protection
Dicot- vascular bundles in a ring

12. Woody Stems Consists of sapwood & heartwood
Heartwood- xylem that no longer transports water, provides support
Sapwood- xylem that still transports water

13. Woody Stems: How Tree Rings Form
Vascular cambium
Layer outside of wood
Create new xylem every year in the spring & the summer (tree rings!)
Indicator of weather
Good season, wider ring
Bad season, narrower ring

14. Woody Stems: Bark Bark- includes cork & phloem
Vascular cambium creates new phloem
Cork cambium produces new cork (bark that we see)

15. Leaf Cross Section
Leaves
Cuticle- waxy covering; prevents drying out and provides support
Stomata- opening for gas exchange
Guard cells- open & close stomata
Vein
Contains xylem & phloem
Xylem- transport water
Phloem- transport sugar
Palisade- packed closely together- photosynthesis
Sponge- open spaces- allow gas exchange within leaf

16. Stomata Opens to allow gas exchange between plant and atmosphere
Open- photosynthesis, at risk to dry out
Closed- no photosynthesis, maintains moisture

17. Water Movement in Plants
Root pressure
Moves water through osmosis
Works up to 1 meter
Capillary Action
Movement due to small area
Cohesion & adhesion
Cohesion- water sticks to itself
Adhesion- water sticks to walls of xylem

18. Water Movement in Plants
Transpirational Pull
Main source of upward water movement in plants
Water evaporates from stomata in leaves
Water moves up plant to replace lost water
Occurs through cohesion & adhesion
If guard cells open longer, greater transpirational pull

19. Food Movement in Plants
Food (glucose) moves downward starting from the leaves
_________: vessel that transports glucose

20. Plant Hormones Have specific receptors that enable specific responses
Auxins
Stimulate cell
elongation & suppresses
growth of lateral (side) buds
Enables plants to
bend toward light

21. Plant Hormones Gibberellin
Stimulate stem elongation by stimulating cell division & elongation

22. Plant Hormones Cytokinin
Stimulates growth of lateral (side) buds and release apical dominance (more growth on sides of plant rather than at the top)
Stimulate flowering

23. Plant Hormones
Abscisic acid (ABA)
Inhibits plant growth (short)

24. Plant Hormones
5. Ethylene
Promotes fruit ripening and flower opening