Introducing plants

1. Section 22-1 Introducing plants

2. Criteria for Kingdom Plantae • Cell type: Eukaryotes. • Cell number: Multicellular. • Cell structure: Cell wall made of cellulose. • Mode of nutrition: Autotrophic. • Carry out photosynthesis using the green pigments chlorophyll a and b. • Some are parasitic or saprobes.

3. Plant Life Cycle All plants have a life cycle with alternation of generations, in which the haploid gametophyte phase alternates with the diploid sporophyte phase. Textbook, page 552

4. Plant Life CycleAlternation of Generations! • Haploid (N) • Gametophyte plant (N) • Produces either sperm or eggs. • (gametes = reproductive cells) • Diploid (2N) • The sperm and egg join to create the Sporophyte plant (2N), which is diploid. • Egg and sperm join to create spores by meiosis.

5. Plant Survival • Sunlightneeded to carry out photosynthesis. • Minerals and water are needed to make new plant parts. • Gas exchange (through photosynthesis and cellular respiration) must occur without losing excessive amounts of water. • Movement of water and nutrients is required for plant energy production and growth.

6. Evolutionary Cladogram of Plants (Angiosperms) (Gymnosperms) (Bryophytes)

7. Overview of the Plant Kingdom The majority of plant life is ______________.

8. Section 22-2 Bryophytes

9. Bryophytes (ex. mosses, liverworts, hornworts) • Life cycles depend on water for reproduction. • Abundant in moist environments (bogs, near streams, in rain forests) because there is novascular tissue. • Sphagnum moss alive is used in gardening, and when compacted (peat) it’s used for fuel. (Angiosperms)

10. Typical Moss Plant Capsule Stalk Rhizoid Sporophyte Stemlike Structure Leaflike Structure Gametophyte

11. Life Cycle of a Moss

12. Section 22-3 Ferns:Seedless Vascular Plants

13. What developed between plant divisions 1 and 2? Vascular Tissue developed! Vascular tissue: specialized tissue to transport water and nutrients throughout the plant.

14. Phylum Pterophyta: Ferns • Ex. horsetails, club mosses, ferns. • Leaves are called fronds. • Undergound stems called rhizomes . • Found in moist, shaded forest areas. • Sori – clusters of sporangia (spores on the underside of fronds).

15. Vascular Tissue • Tracheidsare specialized cells that can move fluids through the plant body, even against the force of gravity. • Xylem(moves water upward). • Phloem(moves nutrients and carbohydrates throughout the plant).

16. Typical Fern Plant

17. Life Cycle of a Fern

18. Section 22-4 Gymnosperms:Seed Plants

19. Gymnosperms: Cone Bearers • Means “naked seed”. • Includes conifers (pines & spruces) and palms (cycads & ginkgoes). • Adapted seed to allow reproduction without water; able survive in dry and extreme temperatures.

20. Reproduction Free from Water • Second evolutionary development of plants = seeds. • Adaptations that allows seed plants to reproduce without water include: • Flowers and cones. • Transfer of sperm by pollination. • Protection of embryos in seeds. • Necessary to meet the challenges of surviving on land.

21. Diagram of a Pine Seed • Embryo • Growing part of seed containing: • Endosperm • Tissue that provides nutrition for the developing seed. • Seed Coat • Protective outer covering of the seed. Embryo Endosperm Seed Coat

22. Reproduction • Germination:early growth stage of a plant embryo. • Dormancy:period of time during which a plant embryo is alive but not growing. • Features that allow seeds to reproduce without water: • Reproduction in cones. • Movement of gametes by pollination. • Protection of embryo in a seed.

23. Pollination • Transfer of pollen from the male reproductive structure to the female reproductive structure.

24. Adaptations • Needles • Winged Seeds

25. Section 22-5 Angiosperms:Flowering Plants

26. Anthophyta: Angiosperms • Dominate plant life. • Flowers are the reproductive organs of plants. • has ovaries (fruit) to protect the seeds. • Attracts animals which help with pollination.

27. Diversity of Angiosperms Can be classified into: • Stems: herbaceous vs. woody. • Lifespans: annuals, biennials, perennials. • monocotyledon vs. dicotyledon.

28. Monocots vs. Dicots

29. Lifespans • Annuals • Complete life cycle in one year. • Biennials • Life cycle takes 2 years • Year one: germinate and grow roots, maybe leaves. • Year two: grow new stems, leaves, and flowers. • Perennials • Live through many years • May die back in winter, but re-grow in the spring (asparagus, peonies, many grasses). • Most have woody stems (palms, trees, honeysuckle).

30. Examples of Monocotyledons(Liliopsida) • Grasses which include grains such as corn and wheat. • Lilies. • Orchids. • Palms.

31. Examples of Dicotylendons(Magnoliopsida) • Roses • Mallows • Tomatoes • Oaks • Daisies

32. Plant Parts • Transport • Roots, stems, leaves. • Energy Production • Leaves. • Reproduction • Flowers.

33. Roots (Transport) • Taproot: primary root grows down from the stem with secondary roots forming. • ex. carrot, potato, radish • Fibrous: small lateral roots that spread out just below surface of the soil. • ex. weeds

34. 4 Root Functions • Absorbs water & nutrients from the soil. • Transports water & nutrients to stem. • Anchors plant to maintain stability. • Stores food and water.

35. Structure of Roots Outermost layer of cells Site of absorption Tissue that stores starch Within cortex; contains cells for transport of water, nutrients, & minerals) Protection of root tip

36. Stems (Transport) • Woody • Thick cell walls that support the plant. • Trees, shrubs, and vines. • Herbaceous • Stems are smooth, supported by hydrostatic pressure (turgor). • Dandilions, zinnias, petunias.

37. Stems

38. 3 Functions of Stems • Transports water & nutrients from roots to leaves. • Supports/produces leaves, branches, fruits/flowers. • Stores food.

39. Capillary action: the tendency of water to rise in a thin tube. The result of the water molecules’ ability to stick to one another (cohesion)and to the walls of the tube (adhesion). Contributes to the movement of water up the cells of the xylem tissue. Transport in Plants

40. Leaves (Transport & Energy Production) • Photosynthesis • Process that plants use to produce their food. • 6CO2 + 6H2O C6H12O6 + 6O2 • Transpiration • Loss of water and exchange of carbon dioxide.

41. Structure of Leaves • Cuticle • Waxy outer surface; retains moisture. • Mesophyll • Middle layer of leaf where photosynthesis occurs. • Palisade layer (upper). • Spongy layer (underside).

42. Epidermis “Skin” of leaf - responsible for gas exchange. Upper and lower. Stomata Outside layer of leaf opening in epidermis where gas and water exchange (controlled by guard cells). Structure of Leaves (cont’d)

43. Turgor pressure (water pressure) Stomata close automatically when supplies of water from roots start to dry up. Guard cells trigger when water is scarce causing stomata to become flaccid and pores close. Gas Exchange in Leaves

44. Leaf Vein Types Parallel Pinnate Palmate

45. Flowers (Reproduction)

46. Structure of Flowers

47. Typical Flower Structure • Petals • Highly colored part of the flower, may contain perfume and/or nectar glands. • Sepals • Small green structures on the base of a flower that protect the flower bud. Image found at: http://biology.clc.uc.edu

48. Male Plant Organ • Stamen contains: • Anther: produces pollen. • Filament: upholds anther.

49. Female Plant Organ • Pistil(carpels) contains: • Stigma: sticky for pollen to attach. • Style: sperm travel to ovary. • Ovary (fruit): stores ovules (eggs).

50. Seed Dispersal • Wind • Water • Animal Flower Pollination • Animals • Wind Factors that affect seed germination: • Temperature • Moisture