Transcript Kingdom Plantae

Kingdom Plantae
BSC 2011C – Fund of Bio II
Spring 2007 – J. Laborda
Introduction
• Botany
• Importance of the Plant Kingdom
– It provides a majority of our food
– It provides a majority of our energy
– Plants produce some of our oxygen
– Plants provide a variety of products
– Plants are also important to us in a sort of
spiritual way, a source of beauty, comfort,
relaxation, etc…
Introduction
• Basic Plant Kingdom Information
– Cellular Structure
• Eukaryotic and Multicellular
• Cell walls are present made of cellulose
• Most have chlorophyll (green) and other pigments
within chloroplasts
• Carry out photosynthesis
• They are autotrophs
Introduction
• Basic Plant Kingdom Information (cont)
– Reproduction
• They reproduce sexually, though many also have
forms of asexual reproduction
Introduction
• Three Major Plant Groups
• The kingdom is currently divided into 10 phyla
– See Appendix D in Campbell/Reece text
• These 10 phyla can be placed into three major
groups
– Nonvascular plants
– Vascular plants without seeds
– Vascular plants with seeds
Introduction
• Three Major Plant Groups (cont)
– Nonvascular plants (Bryophytes)
• Lack vascular tissues
• There are currently three phyla in this group
– Phylum Hepatophyta (liverworts)
– Phylum Anthocerophyta (hornworts)
– Phylum Bryophyta (mosses)
Introduction
• Three Major Plant Groups (cont)
– Vascular plants without seeds
• A seed contains a young plant and stored food
inside a protective seed coat
• There are currently two phyla in this group:
– Phylum Lycophyta (lycophytes)
– Phylum Pterophyta (ferns, horsetails, whisk ferns)
Introduction
• Three Major Plant Groups (cont)
– Vascular plants with seeds (contains two subgroups)
• Non-flowering plants (Gymnosperms)
–
–
–
–
Phylum Ginkgophyta (ginkgo)
Phylum Cycadophyta (cycads)
Phylum Gnetophyta (gnetophytes)
Phylum Coniferophyta (conifers)
• Flowering plants (Angiosperms)
– Phylum Anthophyta
Plant Classification
• Nonvascular Plants
– At one time all nonvascular plants were
classified in phylum bryophyta
– The word bryophyta means “moss plant”
– This group (nonvascular plants) contains the
mosses (Bryophyta), liverworts (Hepatophyta), and
hornworts (Anthocerophyta)
– Epiphytes
Mosses
Moss
Moss
Moss
Plant Classification
• Nonvascular Plants (cont)
• Life cycle of a moss:
– It illustrates “alternation of generations”
– The two generations (act of producing) are:
» Gametophyte generation - multicellular
haploid form that mitotically produces
haploid gametes that unite and grow into
the sporophyte generation
» Sporophyte generation – the multicellular
diplid form that results from a union of
gametes and that meiotically produces
haploid spores that grow into the
gametophyte generation
Figure 29.8 The life cycle of a Polytrichum
moss (layer 3)
Raindrop
Key
Male
gametophyte
Sperm
“Bud”
Page 581
Haploid (n)
Diploid (2n)
Antheridia
Protonemata
“Bud”
Gametophyte
Egg
Spores
Gametophore
Female
gametophyte
Peristome
Arcl
egonia
Rhizoid
Sporangium
MEIOSIS
Mature
Mature
sporophytes
sporophytes
Seta
FERTILIZATION
Capsule
(sporangium)
Calyptra
Zygote
(within archegonium)
Embryo
Sporophyte
Foot
Archegonium
Young
sporophytes
Capsule with
peristome (LM)
Female
gametophytes
Antheridia
Archegonia
Young
sporophyte
Plant Classification
• Nonvascular Plants (cont)
– Economic importance of the nonvascular
plants (bryophytes)???
Plant Classification
• Vascular Plants Without Seeds
– These are plants with vascular tissues
for transporting water and minerals
throughout the plant
– This group (vascular plants w/o seeds)
contains the lycophytes (Lycophyta), ferns,
horsetails, & whisk ferns (Pterophyta)
– Phylum Lycophyta (lycophytes)
– Phylum Pterophyta (ferns, horsetails, whisk ferns)
Lycophytes
(club mosses,
spike mosses,
quillworts)
Ferns (pterophytes – true ferns
?filicinophytes?)
Horsetails
(pterophytes
–
?sphenophytes?)
Whisk ferns pterophytes
(?psilophytes?)
Whisk fern in San Fran
Psilotum nudum bearing sporangia
Plant Classification
• Vascular Plants Without Seeds (cont)
– They do not produce seeds, but rather
spores
– Spores are a single cell with a protective
coat
• The life cycle of a fern
1 Sporangia release spores.
Most fern species produce a single
type of spore that gives rise to a
bisexual gametophyte.
Key
2 The fern spore
develops into a small,
photosynthetic gametophyte.
3 Although this illustration
shows an egg and sperm
from the same gametophyte,
a variety of mechanisms
promote cross-fertilization
between gametophytes.
Haploid (n)
Diploid (2n)
Antheridium
Page 585
Spore
MEIOSIS
Young
gametophyte
Sporangium
Archegonium
Mature
sporophyte
New
sporophyte
Sperm
Egg
Zygote
Sporangium
FERTILIZATION
Sorus
6 On the underside
of the sporophyte‘s
reproductive leaves
are spots called sori.
Each sorus is a
cluster of sporangia.
Gametophyte
Fiddlehead
Figure 29.12
5 A zygote develops into a new
sporophyte, and the young plant
grows out from an archegonium
of its parent, the gametophyte.
4 Fern sperm use flagella
to swim from the antheridia
to eggs in the archegonia.
Fern Antheridium
Fern Archegonium
Fern sori
 Fern
sporangia
Plant Classification
• Vascular Plants With Seeds
– Non-flowering plants (Gymnosperms)
• The seeds of a gymnosperm are not
enclosed in an ovary
• They lie on tiny shelves
–
–
–
–
Phylum Ginkgophyta (ginkgo)
Phylum Cycadophyta (cycads)
Phylum Gnetophyta (gnetophytes)
Phylum Coniferophyta (conifers)
Plant Classification
• Vascular Plants With Seeds (cont)
– Non-flowering plants (Gymnosperms) (cont)
• Phylum Coniferophyta
• Several families of conifers in this phylum
–
–
–
–
Pine family: pines, cedars, spruces, furs
Cypress family: cypresses & junipers
Yew family: yews
Redwood family: redwoods, sequoias, bald cypresses
(have needles instead of scales like the Cypress Family)
The Life Cycle of a Pine
Key
Haploid (n)
Diploid (2n)
Ovule
Megasporocyte (2n)
Ovulate
cone
Pollen
cone
Integument
Longitudinal
section of
ovulate cone
Micropyle
Microsporocytes
(2n)
Mature
sporophyte
(2n)
Pollen
grains (n)
(containing male
gametophytes)
MEIOSIS
Longitudinal
section of
pollen cone
Megasporangium
Germinating
pollen grain
Sporophyll
MEIOSIS
Surviving
megaspore (n)
Microsporangium
Seedling
Germinating
pollen grain
Archegonium
Egg (n)
Female
gametophyte
Seeds on surface
of ovulate scale
Germinating
pollen grain (n)
Food reserves
(gametophyte
tissue) (n)
Seed coat
(derived from
parent
sporophyte) (2n)
Discharged
sperm nucleus (n)
Pollen
tube
Figure 30.6
Embryo
(new sporophyte)
(2n)
FERTILIZATION
Egg nucleus (n)
Integument
Plant Classification
• Vascular Plants With
Seeds (cont)
– Non-flowering plants
(Gymnosperms) (cont)
• Phylum Cycadophyta
(cycads)
– e.g., Sago palm – female
pic above right, see p.
594 for a great pic of a
male cycad
– About 130 species left
today…much more
diverse in the past
Plant Classification
• Vascular Plants With Seeds
(cont)
– Non-flowering plants
(Gymnosperms) (cont)
• Phylum Ginkgophyta (ginkgos)
– Ginkgo biloba is the only extant
species
» Male & female plants are
separate, females put out a
real bad smell
» Males are prized as an
ornamental
» The fan-shaped leaves turn
gold in autumn
Ginkgo biloba
Plant Classification
• Vascular Plants With Seeds (cont)
– Non-flowering plants (Gymnosperms) (cont)
• Phylum Gnetophyta (gnetophytes) (only 3 families)
– EPHEDRACEAE
» Ephedra 40 species. Europe to China, Mexico and US,
S. America.
– GNETACEAE
» Gnetum 28 species. Indomalesia, amazonian S. America,
tropical W. Africa.
– WELWITSCHIACEAE
» Welwitschia One species (W. mirabilis) of Angola and SW
Africa.
Ephedra viridis
Ephedra sinica
Gnetum
Welwitschia mirabilis
Plant Classification
• Vascular Plants With Seeds
– Flowering plants (Angiosperms)
• Seeds enclosed in an ovary
• Only one phylum – P. Anthophyta
• Mature ovary called a “fruit”
– E.g., oranges, tomatoes, corn kernels, pea
pods
– Only one phylum = Phylum Anthophyta
Fruits
Life Cycle of an Angiosperm
Key
Haploid (n)
Diploid (2n)
Microsporangium
Anther
Microsporocytes (2n)
Mature flower on
sporophyte plant
(2n)
MEIOSIS
Microspore (n)
Ovule with
megasporangium (2n)
Generative cell
Tube cell
Male gametophyte
(in pollen grain)
Ovary
Pollen
grains
MEIOSIS
Germinating
Seed
Stigma
Megasporangium
(n)
Embryo (2n)
Pollen
tube
Sperm
Endosperm
(food
Supply) (3n)
Surviving
megaspore
(n)
Seed
Seed coat (2n)
Style
Female gametophyte
(embryo sac)
Antipodal cells
Polar nuclei
Synergids
Egg (n)
Pollen
tube
Zygote (2n)
Nucleus of
developing
endosperm
(3n)
Pollen
tube
Egg
Nucleus (n)
Sperm
(n)
FERTILIZATION
Discharged
sperm nuclei (n)
Generic Flower
Carpel
Stigma
Anther
Style
Stamen
Ovary
Filament
Petal
Sepal
Receptacle
Ovule
Plant Classification
• Vascular Plants With Seeds
– Flowering plants (Angiosperms) (cont)
• Phylum Anthophyta – divided into two
classes:
– Class Monocotyledoneae (monocots)
– Class Eudicotyledonae (eudicots) (the old
Dicotyledonae – dicots) [see p. 602-603]
Monocots
Dicots
Seeds
One cotyledon (seed
leaf)
Two cotyledons
Leaves
Parallel venation
Netted venation
Stems
Vascular tissue scattered Vascular tissue usually
arranged in ring
Roots
Usually fibrous
Usually a taproot
Pollen
Pollen grain with one
opening
Pollen grain with three
openings
Flower parts usually in
multiples of three
Flower parts usually in
multiples of four or five
Flowers
Monocot
Eudicot - Dicot
Monocot = fibrous
Eudicot = tap
Monocot pollen
Plant Anatomy
• Introduction
– Plant parts can be termed as “woody” or
“herbaceous”
• Woody parts
• Herbaceous parts
– Whole plants can be termed as “woody” or
“herbaceous”
• Herbaceous plants
• Woody plants
Plant Anatomy
• Plant Organs
– Vegetative organs
– Reproductive organs
Plant Anatomy
• Plant Tissues
– Meristematic tissues = all one type of cells able to
carry on mitosis
• Apical meristem
• Lateral meristem
– Vascular tissues = made of more than one type of
cell. They conduct water and dissolved materials
• Xylem carries water and dissolved ions from the roots to
stems and leaves
• Phloem carries dissolved sugars from the leaves to all other
parts of the plant
Plant Anatomy
• Plant Tissues (cont)
– Structural tissues =
tissues that carry on
photosynthesis and/or
form the structural
parts of plants
• E.g., Epidermis (covers
& protects) in more
herbaceous plants
• E.g., Periderm – Cork
tissues (protects,
waterproofs) replaces
epidermis in woody
plants
Plant Anatomy
• The Leaf
– Probably two most important functions:
• Trapping energy of sun
• Photosynthesis (production of sugars)
Plant Anatomy
• The Leaf (cont)
– Cuticle
– Epidermis
– Chloroplasts
– Stomata w/guard
cells
Falling Leaves
• Deciduous Trees
– Have an abscission layer at base of petiole
– Leaf scar
– Loss of green color due to lack of water to
leaves during death of abscission layer…less
bountiful colors will show through as result
• Some colors, such as red, blues, violets only are
produced when temps around 40 degrees
• Some species do not produce other pigments…so
when chlorophyll is lacking, they appear brown
due to the tannic acid in all trees
Falling Leaves
• Evergreens
– Most coniferous trees do not lose leaves till
Spring when new leaves have already
grown…thus appear always green
Plant Growth Time Factors
• Annual plants
– Sprout, grow, flower, and produce seeds in one
growing season
– Most herbaceous plants are annuals
• Biennial plants
– Sprout & grow in first growing season
– Flowers & produces seeds in second growing season
• Perennial plants
– Grows year after year
– Most woody plants are perennials
– Some herbaceous plants are perennials
The Root
• Functions of Roots
– Anchoring
– Absorption
– Transportation
– Food Storage
The Root
• Root Systems
– Taproot system (e.g.,
carrots, oak trees)
– Fibrous root system
– Adventitious roots
arising from stems
The Root
• Growth of a Root
– Longitudinal section
of a root tip
•
•
•
•
Root cap
Meristematic region
Elongation region
Maturation region
The Root
• Growth of a Root
– Primary tissues
(made during the
primary growth of a
root)
•
•
•
•
Epidermis
Cortex
Endodermis
Vascular tissues
– Vascular cylinder
in eudicots
– Spread out in
monocots
The Root
• Growth of a Root
– Primary tissues (made
during the primary
growth of a root)
• Vascular tissues (cont)
–
–
–
–
Xylem
Phloem
Cambium
Pericycle
The Stem
• Functions of Stems
– Manufacture and display leaves
– Conduct materials to leaves for
photosynthesis and growth, and to roots for
growth
– Most carry on photosynthesis when young,
and a few as adults (e.g., cacti)
The Stem
• External Anatomy of a
Stem
– Bud scales
– Apical bud (terminal
bud)
– Lateral bud
– Internode
– Bud scale scars
– Leaf scar
– Lenticels
End of Plant Unit
Some additional material covered
in lab