Plant Diversity Chapter 22. 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,
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
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)