Chapter 21-24

1. Chapter 21-24 WHAT ARE PLANTS & HOW ARE THEY CLASSIFIED

2. Section Objectives: • List the characteristics of plants. • Identify some of the plant kingdom divisions. • Compare and contrast characteristics of the different groups of plants.

3. BOTANY The study of plants

4. Plant Characteristics • Multicellular eukaryotes • Autotrophic: produce their own food (glucose) through the process of photosynthesis and store food in the form of starch. • Plant cells have thick cell walls made of cellulose. • The stems and leaves of plants have a waxy waterproof coating called a cuticle. • Contain chloroplast that contain pigment chlorophyll

5. Plant Characteristics Cont.There are three main organs in a plant1. Roots: Functions; A. absorb water and nutrients from soilB. anchor plants into the groundC. hold plant upright and prevent being knocked over by wind or rain

6. Organs in a Plant Cont.2. Stems: Functions;A. holds leaves up to the sun; all plants compete for sun3. Leaves: Functions;A. They are broad to capture more sunlightB. They have a waxy coat (cuticle) to hold in H2OC. They have pores to allow CO2 to enter and O2 to exit

7. Other Parts and Processes of Seed Plants:4. Pollen Grain – male gamete of seed plants is contained in this structure5. Pollination – the carrying of pollen from male to female by wind, insects, birds and small animals

8. Other Parts and Processes of Seed Plants Cont:6. Seeds: structures that protect the zygotes of plants7. Embryo – tiny plant after fertilization8. Seed Coat: protects the seed from drying out, this allows survival in a variety of climates

9. Plant Kingdom Breakdown Nonvascular (mosses & liverworts) • Plant Seedless Spore Bearing (ferns) Vascular Plant Conifers (gymnosperm) Seed Bearing Flowering (angiosperms) Monocot Dicot

10. Phylogeny of Plants • 1st division: do they have vascular tissue: vascular or nonvascular. • 2nd division: does it produces seeds: non-seed plants and seed plants. • 3rd division: is seed bearing plants a cone bearing or flower bearing: gymnosperms or angiosperms. • 4th division: angiosperms are divided: monocots and dicots.

11. What is a nonvascular plant? • No vascular tissue • Limited to moist habitats by streams and rivers or in temperate and tropical rain forests. • Small in size and shape • Mosses

12. Phylum Bryophyta: nonvascular plants • Bryophytes,the mosses, are nonvascular plants that rely on osmosis and diffusion to transport materials. • Moss plants are usually low to the ground and have leaflike structures • Simplest form of plants • Found in moist areas that are shaded • Reproduce by spores

13. Difference betweenvascular & nonvascular plants • Vascular plants can live farther away from water than nonvascular plants. • Vascular plants can grow much larger than nonvascular plants.

14. Vascular Plants • Contain vascular tissue which is xylem and phloem in the stem of the plants • Xylem transports water and dissolved substances from the roots to other parts of plant • Phloem transports dissolved sugar from leaves (photosynthesis) to the rest of plant

15. Phylum Tracheophytes • All vascular plants (have xylem and phloem) • Can live in drier climates than nonvascular • Uses roots to absorb food and minerals and uses vascular tissue to transport it

16. SEEDLESS VASCULAR PLANTS • Ferns are the most well-known and diverse group of non-seed vascular plants. • They have leaves called fronds. • Reproduce by spores on their leaves. • Need water to reproduce so they are found in moist areas.

17. SEED BEARING VASCULAR PLANTS • Seed plants produce seeds • A seed consists of an embryonic plant and a food supply covered by a hard protective seed coat. • All seed plants have vascular tissues. • These tend to adapt well to their environment

18. 2 Divisions of Seed Bearing • Gymnosperms/Conifers • Angiosperms/Flowering Plants

19. Gymnosperms • Gymnosperms seeds sits on the scales • Scales – special leaves that contain male and female reproductive structures • Cones – scales that are grouped into larger structures, there are male and female cones

20. Cones Cont. • A. Male cones produce gametophytes called pollen (starts out closed and when opened it releases pollen) • Female cones produce gametophytes called eggs (starts out closed and when opened it releases seeds, much bigger than male cones) • Female cone holds the seeds that develop

21. 3 Classes Gymnosperms • 1. Cyads • 2. Ginkgoes • 3. Conifers

22. Cycads • Palmlike plants present with the dinosaurs in the Triassic Period • They grow naturally in Mexico, West Indes, Florida, Parts of Asia, Africa, and Australia

23. Ginkgoes • Were alive during the dinosaur period. • There is only 1 living species (Ginko biloba) • The oldest living seed plant

24. Conifers • Commonly called evergreens, the most abundant gymnosperm on Earth • Examples: pines, spruce, fir, cedar, sequoias, and redwoods • Leaves are long and thin and are called needles

25. Conifers/Gymnosperms • Cone-bearing trees such as pine, fir, cypress, and redwood. • Cones are scaly structures that support male or female reproductive structures. • Their leaves that are needlelike or scaly.

26. Reproduction in the Conifers • The reproductive structures of most conifers are produced in cones. • Most have male and female cones on different branches of the same tree. • The male cones produce pollen, female cones are much larger and stay on the tree until the seeds have matured.

27. Evergreen vs. Deciduous trees • Most conifers are evergreen —plants that retain some of their leaves for more than one year. • Deciduous plants drop all their leaves each fall or when water is scarce or unavailable. It reduces water loss. A tree with no leaves cannot photosynthesize & must remain dormant during this time.

28. Angiosperms • Commonly called the flowering plants, are the largest, most diverse group of seed plants living on Earth. • They produce flowers from which fruits develop. • A fruit usually contains one or more seeds. Ex: apples, oranges, beans, peas, pumpkins, tomatoes, eggplants • 2 classes: monocotyledons (monocots) & dicotyledons (dicots)

29. Monocots • Examples: corn, wheat, lilies, daffodils, orchids; monocots have only 1 seed leaf

30. Dicots • Examples: roses, clover, oaks, tomatoe, daisies; dicots have 2 seed leaves

31. Monocot and Dicot Characteristics • Monocot: • Veins are parallel • Flowers, petals and parts in 3’s or multiples of 3 (3,6,9,12) • Dicots • Veins form branching network • Flowers, petals, and parts occur in 4’s or 5’s or multiples (4,8,12 or 5,10,15)

32. Adaptations in Angiosperms • Angiosperms have roots, stems, and leaves. • They produce flowers and form seeds enclosed in a fruit. • A fruit develops from a flower’s female reproductive structure(s).

33. MONOCOTS • One cotyledon (seed leaf) • Parallel venation in the leaves • Fibrous root system • Flower parts in multiples of 3 • Vascular tissue is arranged in a scattered bundle

34. DICOTS • Two cotyledons (seed leaf) • Net venation in the leaves • Taproot root system • Flower parts in multiples of either 4 or 5 • Vascular tissue is arranged in a circular ring

35. Other Info. • Vector Pollination – pollination by animals • The bitter taste of unripe fruit is to protect fruit from being eaten by animals until ripe when seeds can be spread • Green fruit is a protective mechanism to hide fruit until its ripe

36. Moncots and dicots Distinguishing Characteristics of Monocots and Dicots SeedLeaves Flower Parts Vascular Bundles in Stems Leaves One cotyledon Usually parallel Scattered Multiples of three Monocots Usually netlike Arranged in ring Multiples of four and five Two cotyledons Dicots

37. Section Objectives: • Describe the alternation of generations in land plants. • Describe sexual reproduction in angiosperms

38. Alternation of Generations Section 24.1 Summary – pages 633-640 • An alternation of generations consists of a sporophyte stage and a gametophyte stage. • Sporophyte stage is the 2n stage and it is asexual reproduction through mitosis • Gametophyte stage is n stage and is sexual division through meiosis.

39. What is a flower? • The process of sexual reproduction in flowering plants takes place in a flower, which is a complex structure made up of several organs.

40. FEMALE Structure of the Flower • Pistil: the female organ of the flower • Ovary: at bottom of the pistil which produced the ovule • Stigma: located at the top of the pistil & is where pollen grains attach to (sticky stigma) • Style: long tube of the pistil & is where pollen grains travel down until they reach the ovule • Ovule: develops into a seed; within the ovary

41. MALE Structure of the Flower • Stamen: the male structure of the flower (contains word men) • Anther: located at top of the stamen & produced pollen • Filament: thin, stem like portion a stamen

42. Pollination • Process of transferring ripe, pollen from anther to stigma • Self pollination: pollen on 1 plant is transferred to the stigma on the same flower • Cross pollination: pollen on 1 flower is transferred to the stigma of another flower

43. Structures of Flowering Plants • Roots: Anchor plants, absorb water & minerals and store food • Stems: Support for leaves, reproductive parts, & transportation part of plant • Leaves: The factories for the plants; Take energy from sun and make sugar • Vascular Tissue: transportation system of the plant

44. Types of Stems • Herbaceous plants: flexible stems and includes most of the annuals • Woody plants: stems rigid & hard and includes most of plants that live from season to season

45. TRANSPIRATION • Process where plants lose water through their leaves