1. Chapter 3: Plants

2. Section 1: An Overview of Plants

3. Plant Cells
Unlike animal cells, plant cells have cell walls, which provide structure and protection
Most plant cells contain the green pigments chlorophyll
Photosynthesis – process where plants use chlorophyll to make food
Chlorophyll is found in a cell structure called chloroplast
Many plant cells contain carotenoids – red, yellow, or orange pigments that are also used for photosynthesis

4. Land plants have different adaptations than aquatic plants
To reduce water loss land plants have cuticles – a waxy, protective layer secreted onto the surface of the plant which holds water in
To increase support land plants have cellulose in their cell walls – a chemical compound that provides structure and support
Land plants reproduce using water-resistant spores and seeds

5. Plant classification
Vascular plants use tubelike structures to carry water and nutrients throughout the plant
Nonvascular plants use other ways to move water and nutrients

6. Section 2: Seedless Plants

7. Nonvascular plants – very small plants that have rhizoids rather than roots
Water is absorbed and distributed directly through cell walls
Grow in damp environments
Reproduce by spores rather than seeds

8. Examples of nonvascular plants:
Mosses – green, leaflike growths arranged around a central stalk
Liverworts – flattened, leaflike bodies
Hornworts – have only one chloroplast in each of their cells
Frequently pioneer species – organisms that are the first to grow in new or disturbed areas and which change environmental conditions

9. Seedless vascular plant – reproduce by spores, but have vascular tissue that carries water and nutrients throughout the plant
Can grow bigger and thicker than nonvascular plants
Ferns – largest group of seedless vascular plants
Have stems, leaves, and roots
Leaves are called fronds
Reproduce by spores found on the back of their fronds

10. Club mosses – needlelike leaves
Horsetails – jointed stem with a hollow center

11. Importance of seedless plants
Fuel – decaying seedless plants are compressed into peat and eventually coal
Soil conditioners
Ferns can be used for weaving material and basketry

12. Section 3: Seed Plants

13. Characteristics of seed plants
Have leaves, stems, roots, and vascular tissue
Reproduce by seeds, which contain an embryo and stored food

14. Leaves trap light and make food through photosynthesis
Epidermis – a thin layer of cells on the upper and lower surfaces of a leaf
May have a waxy cuticle coating
Stomata – mall openings in the epidermis that allow carbon dioxide, water, and oxygen to enter and exit a leaf
Each stoma is surrounded by two guard cells that open and close it

15. Palisade layer – contains chloroplasts, where most food is made
Spongy layer – loosely arranged cells and air

16. Stems allow the movement of materials between leaves and roots
Usually above ground
Support the branches, leaves, and flowers
May store food

17. Two kinds: Herbaceous stems – soft and green
Woody stems – hard, rigid, and woody

18. Roots collect water and nutrients from the ground
Roots anchor plants so they don’t blow away
May store food or water

19. Vascular tissue
Xylem tissue – transports water from the roots throughout the plant
Phloem tissue – moves food from where it is made to other parts of the plant
Cambium tissue – produces new xylem and phloem cells

20. Gymnosperms – vascular plants that produce seeds that are not protected by fruit
Oldest trees alive
Have no flowers
Leaves are needlelike or scalelike, evergreens
Four divisions: conifers, cycads, ginkgoes, and gnetophytes
Conifers reproduce by male and female cones

21. Angiosperms – vascular plants that flower and have fruit that contains seeds
Fruit develops from flowers
Most fruit contains seeds

22. Two groups:
Monocots – have one cotyledon used for food storage inside their seeds
Dicots – have two cotyledon inside their seeds

23. Different angiosperms have different life cycles:
Annual – the plant’s life cycle is completed in one year
Biennial – the plant’s life cycle is completed in two years
Perennial – takes more than two years to grow to maturity

24. Human life depends on seed plants
Wood for construction and paper products comes from conifers
Angiosperms form the basis of diets for most animals, including humans