chapter 5 gases - eip biology · 2018. 11. 5. · title: chapter 5 gases author: bio_lab_eip...
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Plant Tissues
Sequestering Carbon in Forests
• Human activities are increasing the amount of CO2 in the
atmosphere exponentially, with potentially catastrophic effects
on Earth’s climate
• Plants remove CO2 from the atmosphere by photosynthesis
and sequester it in their tissues
• Carbon locked in molecules of wood and other durable plant
tissues can stay out of the atmosphere for centuries
Wood
• Carbon is a major part
of cellulose and lignin
that reinforce
specialized cells and
structures that allow a
woody plant to grow tall
Organization of the Plant Body
• Most flowering plants have aboveground shoots, including
stems, leaves, and flowers
• Most kinds also have below-ground roots
• Monocots and eudicots differ in tissue organization
The Basic Body Plan
• Pipelines inside stems conduct water, nutrients, and
photosynthetically produced sugars between leaves and roots
• Roots absorb water and dissolved minerals, and usually serve
to anchor the plant; some plants have specialized root cells
that store carbohydrates
Three Plant Tissue Systems
• Ground tissue system
• Makes up the bulk of the plant body
• Stores materials, functions in photosynthesis, and
structurally supports the plant
• Vascular tissue system
• Tubes distribute water and nutrients through a plant body
• Dermal tissue system
• Covers and protects the plant body
• Includes simple and complex tissues
Body Plan of a Tomato Plant
• Vascular tissues
conduct water and
solutes
• Ground tissues make
up the plant body
• Dermal tissue covers
root and shoot surfaces
Fig. 25.2, p. 398
lateral root
stem
withered seed leaf (cotyledon)
seeds
in fruit
flowerdermal tissues
vascular tissues
ground tissues
shootsroots
node
root tip
primary root
lateral bud
shoot tip (terminal bud)
leaf
Body Plan
of a Tomato
Plant
Eudicots Versus Monocots
Tissues and other characteristics are organized differently in
monocots and eudicots:
• Seeds
• Flowers
• Leaves
• Pollen
• Vascular Bundles
Eudicots Versus Monocots
• Monocots and eudicots are named after their cotyledons
• The primary leaf in the embryo or the “seed leaf”
• They may become the first leaves of a seedling
Fig. 25.4a.1, p. 399
In seeds, two cotyledons
(seed leaves of embryo)
A EudicotsEudicot and
Monocot
Cotyledons
Fig. 25.4b.1, p. 399
B MonocotsEudicot and
Monocot
Cotyledons
In seeds, one cotyledon
(seed leaf of embryo)
Cotyledons
Fig. 25.4a.2, p. 399
Flower parts in fours or fives
(or multiples of four or five)
Eudicot Flowers
Fig. 25.4b.2, p. 399
Flower parts in threes
(or multiples of three)
Monocot Flowers
Eudicot and Monocot Flowers
Fig. 25.4a.3, p. 399
Leaf veins usually forming
a netlike array
Eudicot Leaves
Fig. 25.4b.3, p. 399
Leaf veins usually running
parallel with one another
Monocot Leaves
Eudicot and Monocot Leaves
Fig. 25.4a.4, p. 399
Pollen grains with three
pores or furrows
Eudicot Pollen
Fig. 25.4b.4, p. 399
Pollen grains with one
pore or furrow
Monocot Pollen
Eudicot and Monocot Pollen
Fig. 25.4a.5, p. 399
Vascular bundles
organized in a ring in
ground tissue of stem
Eudicot
Vascular
Bundles
Fig. 25.4b.5, p. 399
Vascular bundles
throughout ground
tissue of stem
Monocot
Vascular
Bundles
Vascular Bundles
Root Systems
Eudicots have a
taproot system.
A main root exists
with branching
subsidiary roots
Main root
Root Systems
Monocots have a
Fibrous root system.
There is no main root.
Root Systems