Explain - Diversity of Plants
Cone-bearing plants760 species
Ferns andtheir relatives11,000 species
Mosses andtheir relatives15,600 species
Floweringplants235,000 species
Form 2 main groups nonvascular and vascular plants
Plant Divisions Bryophytes
(Nonvascular) Do not contain
specialized conducting tissues
Live in water or moist environments
Examples: moss, liverworts, and hornworts
Tracheophytes
(Vascular) They contain vascular
tissue: xylem and phloem
Examples: ferns, conifers, and flowering plants.
Bryophytes (Mosses) Nonvascular No roots, stem,or leaves Transport of water is by
osmosis Short in height (1-5 cm.) Haploid gametophyte is
dominant Diploid sporophyte is
small
Tracheophytes Vascular Plants The xylem conducts water up The phloem conducts food (sugar) down The sporophyte generation is dominant Vascular Seedless Plants (Spores)
and
Vascular Seed Plants
Vascular Seedless Plants Ex. Ferns Contain horizontal
stems, just under the soil, called rhizomes.
The roots grow from the rhizomes
The leaves are called fronds which contain the spores.
Requires H2O for sperm to swim to egg
Evolution of the Gametophyte and the Sporophyte
Gametophyte (N)
Sporophyte (2N)
Bryophytes Ferns Seed plants
Vascular Seed Plants Gymnosperms Nonflowering Bear seeds on the
upper surface of scales inside of cones
Contain true roots, stems, and leaves
Examples Conifers, Pines
Angiosperms Flowering plants Flower is a group of
modified leaves used for sexual reproduction; seeds found in fruit
Contains true roots,stems, and leaves
Examples: rose, lily, oak, maple, pea, and grass
Gymnosperms Leaves are needle-
like Most are evergreen They are called soft
wood. Reproductive
structure is a cone or cone-like structure.
Angiosperms Broad leaf plants Most are deciduous Called hardwood They are divided into
two groups based on the number of seed leaves (cotyledons) they contain.
Haploid (N)
Diploid (2N)
MEIOSIS
FERTILIZATION
Ovule
Anther (2N) Pollen grains (N)(male gametophyte)
Pollentubes
Haploid cell(N)
Embryo sac (N)(female gametophyte)
Egg cell
SpermPollen tube
Endosperm nucleiEndosperm(3N)
Zygote(2N)FruitSeed coat
Endosperm
Embryo(2N)Seedling (2N)
(new sporophyte)
Maturesporophyte
Ovary
Style
Stigma
Life Cycle of Angiosperms
Monocotyledons “Monocots” 1 cotyledon Parallel veins on leaves Fibrous roots Flowers in multiples of 3 Ex) grass, corn
Dicotyledons “Dicots” 2 cotyledons Netted veins Tap root Flowers, 4’s or 5’s Ex) Peanuts, green beans
Seed Germination Concept Map
that
in
have
that
have
SeedGermination
Remains withthe seed
Emergeabove ground
Remainbelow ground
Monocots Dicots
1 Cotyledon 2 Cotyledons
Comparing Wind-pollinated and Animal-pollinated PlantsComparing Wind-pollinated and Animal-pollinated Plants
Characteristics
Pollination method
Relative efficiency of pollination method
Plant types
Reproductive organs
Adaptations that promote pollination
Characteristics
Pollination method
Relative efficiency of pollination method
Plant types
Reproductive organs
Adaptations that promote pollination
Wind-pollinatedPlants
Wind pollination
Less efficient
Mostly gymnosperms and some angiosperms
Cones
Pollination drop
Wind-pollinatedPlants
Wind pollination
Less efficient
Mostly gymnosperms and some angiosperms
Cones
Pollination drop
Animal-pollinated Plants
Vector pollination
More efficient
Angiosperms
Flowers
Bright colors, sweet nectar
Animal-pollinated Plants
Vector pollination
More efficient
Angiosperms
Flowers
Bright colors, sweet nectar
The flower: the defining structure of angiosperms
Reproductive structure: pollen transfer; specialized shoot with modified leaves
Sepals: enclose flower before it opens
Petals: attract pollinators Stamens: male; anther
(produces pollen), filament Carpel or Pistil: female;
stigma, style, ovary, ovules
Flower Types Perfect Perfect flowers
contain both male and female parts on the same flower.
Also called monoecious
Imperfect Imperfect flowers are
missing one of the reproductive parts.
Also called dioecious.
Haploid (N)
Diploid (2N)
MEIOSIS
FERTILIZATION
Ovule
Anther (2N) Pollen grains (N)(male gametophyte)
Pollentubes
Haploid cell(N)
Embryo sac (N)(female gametophyte)
Egg cell
SpermPollen tube
Endosperm nucleiEndosperm(3N)
Zygote(2N)FruitSeed coat
Endosperm
Embryo(2N)Seedling (2N)
(new sporophyte)
Maturesporophyte
Ovary
Style
Stigma
Life Cycle of Angiosperms
Hormone-producing cells
Target cellsMovement of hormone
Hormone Action on PlantsHormone Action on Plants
A.A. AuxinsAuxins1.1. Auxins and PhototropismAuxins and Phototropism
2.2. Auxins and GravitropismAuxins and Gravitropism
B.B. Cytokinins – Cytokinins – stimulate cell division, growth of lateral stimulate cell division, growth of lateral buds, cause dormant seeds to sproutbuds, cause dormant seeds to sprout
C.C. Gibberellins – Gibberellins – growth hormone that stimulates cell growth hormone that stimulates cell elongation, increase the rate of seed elongation, increase the rate of seed germination and bud developmentgermination and bud development
D. Ethylene Gas – D. Ethylene Gas – causes fruit causes fruit to ripen and withering of flowers after to ripen and withering of flowers after fertilization.fertilization.
Plant HormonesPlant Hormones
Control Tipremoved
Opaquecap
Clearcap
Opaque shiedover base
Highconcentration
of auxin
Lowconcentration
of auxin
Auxins and PhototropismAuxins and Phototropism
Plant ResponsesPlant ResponsesA.A. TropismsTropisms
1.1. Gravitropism – response to Gravitropism – response to gravity gravity
2. Phototropism – response to 2. Phototropism – response to lightlight
3.3. Thigmotropism – response to Thigmotropism – response to touchtouch
B.B.Photoperiodism – plants Photoperiodism – plants response to periods of light response to periods of light and darknessand darknessShort-day plantsShort-day plantsLong-day plantsLong-day plants
Photoperiodism in PlantsPhotoperiodism in Plants
Midnight
Noon
Long Day
Midnight
Noon
Short Day
Midnight
Noon
Interrupted Night
Short-Day Plant Long-Day Plant