Everything you ever wanted to know about ... Plants

1. Everythingyoueverwanted to know about ... Plants

2. Plant Facts An acre of trees can remove about 13 tons of dust and gases every year Onions contain a mild antibiotic that fights infections, soothes burns, tames bee stings and relieves the itch of athletes foot Of the more than 260,000 different species of plants, the vast majority are flowering plants  84% of an apple and 96% of a cucumber is water

3. Evolution of Plants One of the most important events in our planet's history was the origin of plant life created conditions that allowed life to continue paved the way for the evolution of higher organisms

4. Plant Overview Plants have three basic structures: roots, stems, and leaves. Important difference between plants and animals plants can lose large parts of itself and still survive an adaptation of plants to protect from herbivores Split into two groups Vascular Non-vascular

5. Important Parts • If you’ve picked or smelled flowers, eaten vegetables, climbed a tree, or pulled up weeds, you already know more about the parts of plants than you may realize. Think about your past experiences with plants, and then list the functions of each of the following parts of a plant: 1. roots 2. leaves 3. stems 4. flowers and cones

6. Parts of a Plant Leaf Stem Root Dermal tissue Vascular tissue Ground tissue

7. Leaf Photosynthetic organ of the plant

8. Leaf Structures Cuticle Thin waxy layer that covers leaf Prevents water loss Epidermis Tough cells that line the upper and lower layers of leaf Stoma: (plural stomata) A pore where water vapor and other gases leave and enter the plant

9. Stem Support Plant Produce leaves and flowers Transport H2O through xylem Transport nutrients through phloem

10. Roots, cont. • Roots have 2 main functions: • Anchor a plant in the ground • Absorb water & dissolved nutrients from the soil

11. Roots • Two main types of roots • Taproots (mostly in dicots) • Primary root grows long and thick while the secondary roots remain small • i.e. Oak Tree • Fibrous (mostly in monocots) • No single root grows larger than the rest • i.e. Grasses

12. Nonvascular Plants Lack true roots, stems, leaves No vessels Small and Simple Water and nutrients are transported mainly by osmosis and diffusion. These processes can only carry items small distances Need Moisture Water required for sexual reproduction.

13. Hornwort Liverwart Moss

14. Vascular Plants Vascular Vessels to transport food and water (phloem and xylem) Roots, stems, and leaves Seeds and no seeds Seeded (Angiosperms) Non-seeded (gymnosperms)

15. Gymnosperms

16. Gymnosperms Gymnos (Greek-naked) and sperma (seed) Key Features Seeded plants whose seeds do not develop with in a sealed container (fruit). Very Successful Why would a seeded plant be more successful than one that is not? Seeds protect the plant embryo, provide nutrients, permit survival during harsh times.

17. Gymnosperms Conifer • Most Successful Gymnosperms • Needle-like or reduced (scale) leaves • Small leaf reduces water loss • Some over 5000 y.o • Cool, dry regions Cycad • Short stems and palmlike leaves • Male (pollen) and Female (seeds) types • Tropics

18. Gymnosperms cont… Gnetophyte: Ephedra Ginkgo • Diverse group of trees, shrubs, and vinves • Produce pollen and seeds in cones that resemble flowers. • Ephedra used for treatment of asthma • Stimulant which constricts blood vessels and increases blood pressure and heart rate.  • Only broadleaf gymnosperm left • Living Fossil- Once thought to be extinct • Ginkgo Biloba (memory or concentration enhancer

19. Angiosperms

20. Angiosperms Produce seeds that develop enclosed within a specialized structure called a fruit Flowers Fruits

21. Flowers Allow more efficient pollination than cones Allows sperm to travel w/o water Angiosperms can have adaptations to ↑ chance of pollination Strongly scented to attract pollen carriers Some are self-pollinators (peas) Small flowers for wind (grass, oak)

22. Fruits Develop from flower Promotes seed dispersal Animals eat fruit…seeds passed through digestion system Other seeds can float on wind/water Provide some protection for seed

23. 2 Types of Angiosperms

24. What is a Monocot? • Has one seed leaf (cotyledon) • Parallel leaf veins • Fibrous roots • Flower parts in 3’s • Vascular tissue scattered • Examples: Grasses, orchids, palm trees

25. What is a Dicot? • Has two seed leaves (cotyledons) • Network of veins in leaves • Primarily tap roots • Flower parts in 4’s or 5’s • Vascular tissue in rings • Examples: onion, roses, peas

26. Familiar Monocots Iris Corn Lily Wheat Grass Lily

27. Familiar Dicots Daisy Rose Apple Blossom Tomato

28. Single cotyledon Two cotyledons Parallel veins Branched veins Floral parts often in multiples of 3 Floral parts often in multiplesof 4 or 5 Vascularbundlesscattered throughout stem Vascularbundlesarranged ina ring Fibrous roots Taproot The angiosperms are a diverse group. There are two classes within the angiosperms : monocotyledonae, or monocots, & dicotyledonae, or dicots. Monocots Dicots Seeds Leaves Flowers Stems Roots

29. Angiosperms • Develop unique reproductive organs known as flowers. • Flowers contain ovaries, which surround and protect the seeds.

30. Angiosperm Reproductive Organs: The Flower Stamen Pistil Stigma Anther Style Filament Ovary Petal Ovule Sepal

31. Angiosperm Reproductive Organs:The Flower • Sepals – Protects the flower while it is developing, surrounds the outside • Petals – Attract insects & other pollinators to the flower • Stamen – The male part of the flower: • Filament – long, thin stalk that supports the anther • Anther – oval sac where male gametophytes called pollen are produced

32. Angiosperm Reproductive Organs:The Flower • Pistils – The female part of the flower: • Ovary – broad base which contains the female gametophtes • Style – long tube entering the ovary • Stigma – at the top of the style, where pollen grains frequently land

33. Pollination • Transfer of mature pollen grains from the anther to the stigma -wind -insects -birds & other animals

34. Fertilization • When a pollen grain lands on the stigma, it germinates and a pollen tube grows down through the style to an ovule (egg) • The sperm travels through the pollen tube to the ovule. The sperm & egg fuse forming the zygote (fertilized egg) –this grows into the plant embryo (cells grow by mitosis)

35. Fertilization • The ovary and zygote (fertilized ovule) develop and ripen. • The ovule forms the seed and the ovary forms the fruit. • A fruit is a ripened ovary

36. Fertilization • Self pollination • Pollen from the same flower • Cross Pollination • Pollen from a different flower • More variation