Slide 1

Plant Diversity Chapter 22

Slide 2

What is a Plant? Plants are the base for the food chain on land. Plants are the base for the food chain on land. Provide shade, shelter and oxygen Provide shade, shelter and oxygen Evolved more than 470 million years ago Evolved more than 470 million years ago Multicellular, Eukaryotes Multicellular, Eukaryotes Cell walls made of cellulose Cell walls made of cellulose Photosynthesis using chlorophyll a and b Photosynthesis using chlorophyll a and b Most are autotrophs; few parasites + saprobes Most are autotrophs; few parasites + saprobes Ex. Trees, shrubs, grasses, mosses and ferns Ex. Trees, shrubs, grasses, mosses and ferns

Slide 3

Life Cycle Haploid (N)-Gametophyte; gamete-producing Haploid (N)-Gametophyte; gamete-producing Diploid (2N)-Sporophyte; spore-producing Diploid (2N)-Sporophyte; spore-producing Produce a new individual by mitosis Produce a new individual by mitosis All plants have both phases, but in different forms All plants have both phases, but in different forms Can reproduce independently of water Can reproduce independently of water Some also reproduce asexually (vegetative) Some also reproduce asexually (vegetative)

Slide 4

Haploid Diploid MEIOSIS Spores (N) FERTILIZATION Sperm (N) Eggs (N) Section 22-1 Generalized Plant Life Cycle Go to Section:

Slide 5

Plant Survival Sunlight Sunlight Water and Minerals Water and Minerals Taken up through the roots Taken up through the roots Movement of Water/Nutrients Movement of Water/Nutrients Make food in their leaves Make food in their leaves Water and nutrients carried upward through tissue from soil Water and nutrients carried upward through tissue from soil Gas Exchange Gas Exchange

Slide 6

Early Plants Evolved from multicellular green algae Evolved from multicellular green algae First plants were dependent on water First plants were dependent on water Similar to todays mosses in structure and growth close to the ground Similar to todays mosses in structure and growth close to the ground Evolved different adaptations for terrestrial environments Evolved different adaptations for terrestrial environments

Slide 7

Cone-bearing plants Ferns and their relatives Seeds Water-Conducting (Vascular) Tissue Section 22-1 Cladogram of Plant Groups Go to Section:

Slide 8

Overview of the Plant Kingdom Divided into four groups based on water- conducting tissues, seeds and flowers Divided into four groups based on water- conducting tissues, seeds and flowers Reproductive structures and body plan are also considered Reproductive structures and body plan are also considered Compare DNA sequences of various species Compare DNA sequences of various species Deep Green (1994)-Evidence that first plants evolved from green algae that lived in fresh water Deep Green (1994)-Evidence that first plants evolved from green algae that lived in fresh water

Slide 9

Cone-bearing plants 760 species Ferns and their relatives 11,000 species Mosses and their relatives 15,600 species Flowering plants 235,000 species Section 22-1 The Diversity of Plants The Diversity of Plants Go to Section:

Slide 10

Bryophytes Nonvascular plants 1) Mosses (in swamps) 1) Mosses (in swamps) Can live in harsh environments Can live in harsh environments Rhizoid-long, thin cells absorb water and minerals and anchor them to the ground Rhizoid-long, thin cells absorb water and minerals and anchor them to the ground 2) Liverworts and 3) hornworts Use osmosis to draw up water Use osmosis to draw up water Water needed for reproduction Water needed for reproduction Act as natural sponge and form peat moss Act as natural sponge and form peat moss

Slide 11

Bryophytes MossesLiverworts Hornworts MossesLiverworts Hornworts http://www.ghettodriveby.com/hornworts/ http://www.ghettodriveby.com/hornworts/

Slide 12

Seedless Vascular Plants Vascular tissue-Specialized to conduct water and nutrients thought he body of the plant Vascular tissue-Specialized to conduct water and nutrients thought he body of the plant Xylem-form of vascular tissue that carries water upward from the roots to every part of the plant Xylem-form of vascular tissue that carries water upward from the roots to every part of the plant Phloem-transports solutions of nutrients and carbohydrates from photosynthesis Phloem-transports solutions of nutrients and carbohydrates from photosynthesis Tree rings in the lower trunk indicate the tree age Tree rings in the lower trunk indicate the tree age Formed by cell division in thin layers inside bark Formed by cell division in thin layers inside bark Width of the bands indicate environmental conditions for each year (Ex. Drought conditions) Width of the bands indicate environmental conditions for each year (Ex. Drought conditions)

Slide 13

Slide 14

Ferns Evolved 350 million years ago Evolved 350 million years ago Roots-Underground organs to absorb water and minerals with water-conducting tissue Roots-Underground organs to absorb water and minerals with water-conducting tissue Leaves-Photosynthetic organ that contain bundles of vascular tissue Leaves-Photosynthetic organ that contain bundles of vascular tissue Veins-Made of xylem and phloem Veins-Made of xylem and phloem Stems-Connect roots and leaves Stems-Connect roots and leaves

Slide 15

Slide 16

Seed Plants Gymnosperms-Seeds on cone surfaces Gymnosperms-Seeds on cone surfaces Conifers, Cycads, Ginkgoes and gnetophytes Conifers, Cycads, Ginkgoes and gnetophytes Angiosperms-Flowering plants with seeds in tissue layers Angiosperms-Flowering plants with seeds in tissue layers Flowers or cones transfer sperm by pollination and protect embryos in seeds Flowers or cones transfer sperm by pollination and protect embryos in seeds Life cycle alternates between gametophytes and sporophyte Life cycle alternates between gametophytes and sporophyte

Slide 17

Seed coat Embryo Stored food supply Seed A B Section 22-4 The Structure of a Seed Go to Section:

Slide 18

Reproduction without Water Cones-sporophyte structures which are seeding bearing for gymnosperms Cones-sporophyte structures which are seeding bearing for gymnosperms Flowers-Seed-bearing structure of angiosperms Flowers-Seed-bearing structure of angiosperms Pollen Grains-Contain male gametophytes Pollen Grains-Contain male gametophytes Seeds-Embryo of seed plant with seed coat and food supply Seeds-Embryo of seed plant with seed coat and food supply Eaten and dispersed by animals or stick to their fur Eaten and dispersed by animals or stick to their fur Fossils from 30 million years ago Fossils from 30 million years ago

Slide 19

A Bee With Pollen On Its Leg

Slide 20

Gymnosperms Cone Bearers / naked seed Cone Bearers / naked seed 1) Gnetophytes: a) Ex. Welwitschia-Namibian desert with large, leathery leaves; spread across the ground 2) Cycads- (Cycadophyta): a) Palm-link plants with large cones b) Appeared during Triassic Period (225 million years ago) c) Grow in tropical and subtropical places c) Grow in tropical and subtropical places

Slide 21

Welwitschia mirabilis, a GnetophyteWelwitschia mirabilis, a Gnetophyte. And Zamia pseudoparasitica, a Cycad. http://www.conifers.org/pinophyta.htm Zamia pseudoparasitica, a Cycad Welwitschia mirabilis, a GnetophyteZamia pseudoparasitica, a Cycad

Slide 22

Gymnosperms Ginkgoes-Only Ginkgo biloba currently exists Ginkgoes-Only Ginkgo biloba currently exists One of the oldest seed plant species alive today One of the oldest seed plant species alive today Cultivated in China and planted around temples Cultivated in China and planted around temples Often planted in urban settings in U.S. due to resistance to air pollution Often planted in urban settings in U.S. due to resistance to air pollution Conifers-(Coniferophyta) Conifers-(Coniferophyta) Ex. Pines, spruces, firs, cedars, sequoias, redwoods Ex. Pines, spruces, firs, cedars, sequoias, redwoods Long, thin leaves (Ex. Pine needles)-reduces surface area, waxy layer Long, thin leaves (Ex. Pine needles)-reduces surface area, waxy layer Most are evergreens with cycling of needles Most are evergreens with cycling of needles

Slide 23

GinkgoGinkgo and Pseudotsuga menziesii, a Conifer. http://www.conifers.org/pinophyta.htm Pseudotsuga menziesii, a Conifer GinkgoPseudotsuga menziesii, a Conifer

Slide 24

Angiosperms Phylum Anthophyta enclosed seed Phylum Anthophyta enclosed seed Cretaceous Period (135 million years ago) arrival Cretaceous Period (135 million years ago) arrival Dominate Earths plant life Dominate Earths plant life Reproduce with flowers or fruits Reproduce with flowers or fruits Ovary develops into fruits to protect seed and for dispersal Ovary develops into fruits to protect seed and for dispersal Fruit-thick wall of tissue surrounding the seed Fruit-thick wall of tissue surrounding the seed

Slide 25

Seed Dispersal By Wind And General Flower Structure http://science.kennesaw.edu/biophys/biodiversity/plants/plpix5.htm

Slide 26

Monocots and Dicots Cotyledons-Seed leaves in the plant embryo Cotyledons-Seed leaves in the plant embryo Monocots-One seed leaf, parallel veins, multiples of 3 floral parts, vascular bundles scattered and fibrous roots Monocots-One seed leaf, parallel veins, multiples of 3 floral parts, vascular bundles scattered and fibrous roots Dicots-Two seed leaves, branched veins, multiples of 4 or 5 floral parts, vascular bundles in a ring and a taproot Dicots-Two seed leaves, branched veins, multiples of 4 or 5 floral parts, vascular bundles in a ring and a taproot

Slide 27

MonocotsDicots Seeds Leaves Flowers Stems Roots Single cotyledon Parallel veins Floral parts often in multiples of 3 Vascular bundles scattered throughout stem Fibrous roots Two cotyledons Branched veins Floral parts often in multiples of 4 or 5 Vascular bundles arranged in a ring Taproot Section 22-5 Comparison of Monocots and Dicots Go to Section:

Slide 28

Monocots and Dicots http://www.emc.maricopa.edu/faculty/farabee/biobk/BioBookPLANTANATII.html

Slide 29

Diversity of Angiosperms Wood plants made of cells with thick cell walls (Trees, shrubs and vines) Wood plants made of cells with thick cell walls (Trees, shrubs and vines) (Ex. Grapes and Ivy vines) (Ex. Grapes and Ivy vines) (Ex. Blueberries and rose bushes) (Ex. Blueberries and rose bushes) Herbaceous plants-No wood production as they grow (Ex. Dandelions, zinnias, sunflowers and petunias) Herbaceous plants-No wood production as they grow (Ex. Dandelions, zinnias, sunflowers and petunias)

Slide 30

Rose Bush, Grape Vine, Zinnias and Petunias http://www.flowers.vg/flowers/petunia01.htm

Slide 31

Diversity of Angiosperms Annuals-Complete a life-cycle within one growing season Annuals-Complete a life-cycle within one growing season (Ex. Marigolds, petunias, pansies, zinnias, wheat and cucumbers) (Ex. Marigolds, petunias, pansies, zinnias, wheat and cucumbers) Biennials-Complete their life cycle in 2 years Biennials-Complete their life cycle in 2 years Year 1-germinate and grow roots & very short stems Year 1-germinate and grow roots & very short stems Year 2-Grow new stems and leaves and produce flowers and seeds Year 2-Grow new stems and leaves and produce flowers and seeds (Ex. Primrose, parsley, celery) (Ex. Primrose, parsley, celery) Perennials-Live for more than 2 years Perennials-Live for more than 2 years (Ex. Asparagus, grasses-herbaceous stems) (Ex. Asparagus, grasses-herbaceous stems) (Ex. Maple trees-wood stem) (Ex. Maple trees-wood stem)

Slide 32

Primrose, Marigolds, Ornamental Grasses http://landscaping.about.com/cs/designexamples1/l/bllandscaping10.htm