1. Chapter 9: Plants

2. Aim: What characteristics do all plants share?

3. Plant Characteristics
Range in size (microscopic to gigantic)
Adapted to nearly every environment on earth
Shared Characteristics:
Most have roots or root-like structures
All need water
Have a cell wall
Contain chlorophyll to aid in photosynthesis

4. Aim: What adaptations have plants made to survive on land?

5. Evolution of Plants
Land plant ancestors were green algae that lived in the sea
Exact origin of flowering plants are not known
There was more sunlight and CO2 on land for plants to use during photosynthesis than in the sea
As plants moved onto land more O2 became available for animals to develop

6. Adaptations of Land Plants
All adaptations enabled plants to survive on land
Cuticle-helps plant conserve water
Cellulose found in the cell wall helps plants support itself and provide structure
Structures developed that distribute water, nutrients and food to all plant cells
Plants developed water-resistant seeds or spores to help them reproduce

7. Aim: How are plants classified?

8. Classification of Plants
2 divisions
Vascular Plants
have tube-like structures that carry water and nutrients to other parts of the plant
2 groups in this division
Seed vascular and seedless vascular
Nonvascular plants
Do not have tube-like structures
Are seedless and have no groups

9. Binomial Nomenclature
Developed by Carolus Linnaeus
Every plant given a unique 2 word name
Ex: Shasta daisy-chrysanthemum maximum

10. Aim: What are the characteristics of nonvascular plants?

11. Nonvascular Plants Do not grow from seeds Few cells thick
Rhizoids anchor them to the ground not roots
Grow in places that are damp
Do not have flowers or cones
Reproduce by spores- waterproof reproductive cell

12. Mosses
Grow in damp areas
Grow on rocks, trees and ground
Some have adapted to live in the desert
Pioneer species
Liverworts
Rootless plants
Flattened leaf-like bodies
Hornworts
Less than 2.5 cm in diameter
Flattened bodies
Have only 1 chloroplast in each cell

13. Aim: What are the characteristics of seedless vascular plants?

14. Seedless Vascular Plants
Reproduce with spores
Has vascular tissue which is made up of long tube-like structures
Vascular tissue carries water, minerals, and food throughout the plant
This enables plants to grow bigger and thicker
Ferns
Largest group
Have stem, leaves and roots
Leaves are called fronds, where spores are found

15. Club Mosses
Related more to ferns than mosses
Needle-like leaves
Spores are produced at the end of the stem in structures like pine cones
Horsetails
Spores produced in a cone-like structure
Stem is jointed and has a hollow center
Stem contains silica-gritty stubstance
Used for polishing objects and sharpening tools

16. Importance of Seedless Plants
Peat, remains of moss, is used as a low-cost fuel in Ireland and Russia
Scientists hypothesize peat could become coal
Nonvascular plants help build new soil
Parts can be eaten as food, such as rhizomes and young fronds
Ferns used as weaving material
Ferns used as landscaping and house plants
Ferns also used as folk medicines

17. Aim: What are the characteristics of seed plants?

18. Characteristics of Seed Plants
Have leaves, stems, roots and vascular tissue
Produce seeds
2 major groups
Most plants are seed plants
Leaves
Organs where photosynthesis occurs
Come in many shapes, sizes and colors
Epidermis covers and protects the leaf
Cuticle-waxy covering

19. Stomata-openings in the epidermis which allows CO2 and water to enter and exit
Guard cells-open and close the stomata
Palisade layer -most of the food is produced by the cells in this layer
Spongy layer -veins containing vascular tissue are found
Stems
Located above ground and support the branches, leaves and reproductive structures

20. Vascular tissue in stems moves material from the roots to the leaves
Some are herbaceous-soft, and green
Trees and shrubs have hard, rigid woody stems
Roots
Water and nutrients enter the plant through the roots and the vascular tissue transports the substances to the other parts of the plant
Act as anchors, to keep plants from being blown away

21. Sometimes all of the roots can be above ground
Can store food
Plants in dry areas have roots that store water
Root tissue absorb oxygen to aid in respiration
Vascular Tissue
Made up of three tissues
Xylem: tubes stacked up on top of each to form a vessel
Vessels transport substances throughout the plant

22. Xylem cell walls help support the plant
Phloem: tubular cells stacked to form tubes
Tubes move food from where it is made to the other parts of the plant
Cambium: tissue that produces the xylem and phloem cells
The growth of new xylem and phloem thicken the stem and roots

23. Aim: What is the difference between gymnosperms and angiosperms?

24. Gymnosperms Vascular plants
Produce seeds, but no flowers or fruit protect the seeds
Leaves are needlelike
Many are evergreens
Cones are reproductive structures
Seeds develop on female cones

25. 4 divisions
Conifers (pines, firs, spruces, redwoods)
Most diverse group
Cycads
Found in tropical regions
Ginkgoes
Pollution-tolerant
Are deciduous
Gnetophytes (joint fir)
More than ½ of species grouped into 1 genus

26. Angiosperms Vascular plant Flowers and produces fruit
More than ½ of known plant species belong to this group
Flowers vary in size, shape and color
Some flower parts develop into a fruit
Most fruits have seeds
2 groups
Moncots
Dicots

27. Monocots
Has 1 cotyledon-used for food storage in the seed
We get foods from them, such as bananas, pineapple
Other examples: lilies and orchids
Flower parts in multiples of three
Leaves are narrow
Vascular tissues run parallel to one another
Vascular bundles are scattered throughout the plant

28. Dicots
2 cotyledon
Produces peanuts, green peas, apples, oranges
Trees: maple, oak and elm
flower parts are in multiples of four or five
Vascular tissues are in a bundle
Vascular bundles occur in rings like the rings of a tree

29. Aim: Why are seed plants important?

30. Importance of Seed Plants
Paper and wood come from gymnosperms
Cotton comes from seed plants
Fruits, bread, potato chips come from seed plants
Diets of most animals come from angiosperms
Refer to Table 1 Pg 260 for products of seed plants