Download Plant Structure and Growth

Plant Structure and Growth
Plant Structure and Growth
Three main organs:
•Roots
•Stems
•Leaves
Plant Structure and Growth
Three main organs:
•Roots
•Stems
•Leaves
(Angiosperms have a fourth
main organ—the flower.)
Plant Structure and Growth
Two types of angiosperms:
Plant Structure and Growth
Two types of angiosperms:
Monocots
Dicots
Plant Structure and Growth
Two types of angiosperms:
Monocots
•One cotyledon
Plant Structure and Growth
Two types of angiosperms:
Dicots
•Two cotyledons
Plant Structure and Growth
Two types of angiosperms:
Monocots
•One cotyledon
•Parallel veins
Plant Structure and Growth
Two types of angiosperms:
Dicots
•Two cotyledons
•Net-like veins
Plant Structure and Growth
Two types of angiosperms:
Monocots
•One cotyledon
•Parallel veins
•Complex
vascular bundles
Plant Structure and Growth
Two types of angiosperms:
Dicots
•Two cotyledons
•Net-like veins
•Vascular
bundles in rings
Plant Structure and Growth
Two types of angiosperms:
Monocots
•One cotyledon
•Parallel veins
•Complex
vascular bundles
•Fibrous roots
Plant Structure and Growth
Two types of angiosperms:
Dicots
•Two cotyledons
•Net-like veins
•Vascular
bundles in rings
•Tap roots
Plant Structure and Growth
Two types of angiosperms:
Monocots
•One cotyledon
•Parallel veins
•Complex
vascular bundles
•Fibrous roots
•Petals x 3.
Plant Structure and Growth
Two types of angiosperms:
Dicots
•Two cotyledons
•Net-like veins
•Vascular
bundles in rings
•Tap roots
•Petals x 4 or 5.
Plant Structure and Growth
Two types of angiosperms:
Monocots
Dicots
•One cotyledon
•Parallel veins
•Complex
vascular bundles
•Fibrous roots
•Petals x 3.
•Two cotyledons
•Net-like veins
•Vascular
bundles in rings
•Tap roots
•Petals x 4 or 5.
Plant Structure and Growth
Roots
•Fibrous roots absorb water well
•Tap roots hold fast in the ground
and store nutrients
•All roots absorb water mostly at the
root tips, through root hairs
•Adventitious roots prop up tall
stems.
Plant Structure and Growth
Roots
•Fibrous roots absorb water well
•Tap roots hold fast in the ground
and store nutrients
•All roots absorb water mostly at the
root tips, through root hairs
•Adventitious roots prop up tall
stems.
Plant Structure and Growth
Stems
•Nodes and internodes
•Axillary bud by each leaf
Plant Structure and Growth
Stems
•Nodes and internodes
•Axillary bud by each leaf
•Terminal bud at the apex
•Apical dominance
Plant Structure and Growth
Stems
•Nodes and internodes
•Axillary bud by each leaf
•Terminal bud at the apex
•Apical dominance
•Stolons are
“runners.”
Plant Structure and Growth
Leaves
•Main photosynthetic organ
•Blade and petiole (stalk)
–simple
–compound
–double compound.
Plant Structure and Growth
Three main tissue systems:
•Dermal
•Vascular (xylem and phloem)
•Ground.
Plant Structure and Growth
Dermal Tissue
•Single layer of cells over the
outside
•Secretes waxy cuticle
Plant Structure and Growth
Vascular tissue
•Xylem carries water up
•Phloem carries food down
•Tracheids and vessel elements in
the xylem are dead at functional
maturity
•Sieve tube members and
companion cells in the phloem are
alive.
Plant Structure and Growth
Ground tissue
•Includes pith and cortex
Plant Structure and Growth
Types of plant cells:
•Parenchyma (unspecialized)
•Collenchyma (support growing
parts of plant)
•Sclerenchyma (support mature
parts of plant)
•Tracheids (xylem, dead at maturity)
•Sieve-tube members (phloem.)
Plant Structure and Growth
Meristems generate cells for new organs
•Apical meristems elongate roots
and shoots.
•Lateral meristems
add girth to woody
plants.
Plant Structure and Growth
Bark includes phloem and periderm.
Periderm includes cork cells, which
form a waxy protective substance.
Plant Structure and Growth
Morphogenesis in plants
Plant Structure and Growth
The Plane and Symmetry of Cell Division
Plant Structure and Growth
The Plane and Symmetry of Cell Division
•A band of microtubules called the
preprophase band (PPB) determines the
plane of cell division
Plant Structure and Growth
The Plane and Symmetry of Cell Division
•A band of microtubules called the
preprophase band (PPB) determines the
plane of cell division
Plant Structure and Growth
The Plane and Symmetry of Cell Division
•A band of microtubules called the
preprophase band (PPB) determines the
plane of cell division.
Plant Structure and Growth
The Plane and Symmetry of Cell Division
•The fas mutant has disorganized
microtubules and grows into a
disorganized plant.
Plant Structure and Growth
The Plane and Symmetry of Cell Division
•The fas mutant has disorganized
microtubules and grows into a
disorganized plant.
Plant Structure and Growth
Orientation of Cell Expansion
Plant Structure and Growth
Orientation of Cell Expansion
•Microfibrils control the direction of cell
expansion
Plant Structure and Growth
Orientation of Cell Expansion
•Microfibrils control the direction of cell
expansion.
Plant Structure and Growth
Orientation of Cell Expansion
•Plants can expand very quickly because
much of the increase in cell volume is
just water in the central vacuole.
Plant Structure and Growth
Morphogenesis and Pattern Formation
Remember the homeotic genes that we
learned about in animals?
Plant Structure and Growth
Morphogenesis and Pattern Formation
Remember the homeotic genes that we
learned about in animals?
Plants have them too.
Plant Structure and Growth
Morphogenesis and Pattern Formation
•Cells need positional information.
Plant Structure and Growth
Morphogenesis and Pattern Formation
•Cells need positional information.
Auxin, a hormone
secreted at the tip
of the plant, is in
less and less
concentration the
further down you
go.
Plant Structure and Growth
Morphogenesis and Pattern Formation
•Cells need positional information.
This establishes
the root end and
the shoot end, and
lets the cell know
how far down it is.
Plant Structure and Growth
Morphogenesis and Pattern Formation
•Cells need positional information.
Another hormone
secreted at the
surface of the
stem is in less
concentration the
further it you go.
This tells the cell
how far inside it is.
Plant Structure and Growth
Morphogenesis and Pattern Formation
•Morphogenesis is controlled by
homeotic genes
Plant Structure and Growth
Morphogenesis and Pattern Formation
•Morphogenesis is controlled by
homeotic genes
Mutations in the
homeotic genes
can cause
“supercompound”
leaves.
Plant Structure and Growth
Plants also undergo phase changes
•Juvenile growth to mature growth
•Vegetative growth to reproductive
growth (flower formation).
Plant Structure and Growth
Parts of a Flower
Plant Structure and Growth
Parts of a Flower
ovule
Plant Structure and Growth
Parts of a Flower
ovary
ovule
Plant Structure and Growth
Parts of a Flower
style
ovary
ovule
Plant Structure and Growth
Parts of a Flower
stigma
style
ovary
ovule
Plant Structure and Growth
Parts of a Flower
stigma
style
ovary
ovule
carpel
Plant Structure and Growth
Parts
of
a
Flower
anthers
Plant Structure and Growth
Parts
of
a
Flower
anthers
filaments
Plant Structure and Growth
Parts
of
a
Flower
anthers
stamens
filaments
Plant Structure and Growth
Parts of a Flower
petals
Plant Structure and Growth
Parts of a Flower
petals
sepals
Plant Structure and Growth
Parts of a Flower
Plant Structure and Growth
Seen from above, these structures are in
four concentric rings or “whorls.”
Sepals
Petals
Stamens
Carpals
Plant Structure and Growth
Their development is controlled by three
homeotic genes called A, B, and C.
Sepals
Petals
Stamens
Carpals
Plant Structure and Growth
Their development is controlled by three
homeotic genes called A, B, and C.
Sepals
Petals
Stamens
A
B
Carpals
C
Wild type flower
A
AB
BC
C
C
CB
BA
A
Mutant lacking A
C
BC
BC
C
C
CB
CB
C
Mutant lacking A
C
BC
BC
C
C
CB
CB
C
Mutant lacking B
A
A
C
C
C
C
A
A
Mutant lacking B
A
A
C
C
C
C
A
A
Mutant lacking C
A
AB
AB
A
A
BA
BA
A
Mutant lacking C
A
AB
AB
A
A
BA
BA
A
Vocabulary Review
monocot
dicot
fibrous root
tap root
adventitious root
node
internode
axillary bud
terminal bud
apical dominance
stolon
blade
petiole
dermal
vascular
ground
xylem
phloem
tracheid
sieve tube member
pith
cortex
apical meristem
lateral meristem
bark
periderm
cork
homeotic genes
preprophase band
fas mutant
auxin
ovary
ovule
style
stigma
carpel
anther
filament
stamen
petal
sepal.