Parts of a Vascular Plant
Objectives:
•Explain the main functions of the
vegetative parts of a plant
•Notes = yellow
Parts of a plant
•The tissues in a plant can be divided into two
main groups:
•Vegetative: Roots, Stems and Leaves
•Reproductive: Seeds (+ fruits and flowers in
angiosperms)
Roots
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Function:
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Anchor a plant to the ground
Absorb water and minerals from the soil
Sometimes store food
Types of Roots
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There are two main types of roots:

Fibrous: Consists of many similarly sized roots
that form a dense tangled mass.

What happens when you try to pull a fibrous root
out of the soil?
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Taproots: Consists of one long thick main root,
with many smaller roots that branch off the main
root. Taproots are often used to store food.
Structure of a Root
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What is the purpose of
the root cap?
What is the purpose of
the root hairs?
Would you expect to
find chloroplasts in
roots? Why?
Stems
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Function:
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Produces branches, leaves and flowers.
Carries substances between the plant’s roots and
leaves.
Provides support for the plant and holds up leaves
so that they are exposed to the sun.
Stem Structure
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Stems consist of vascular tissue as well as
many other supporting cells.
The vascular tissue in a plant consists of

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Xylem: flows up from root to leaves. Xylem sap
consists of water and inorganic ions. The word
xylem is derived from the Greek word for wood.
Phloem: flows down from leaves to roots. Phloem
carries the product of photosynthesis (sucrose) to
the parts of the plant that need it. The word phloem
is derived from the Greek word for bark.
Types of Stems

Herbaceous Stems: Stems with no wood. Often
soft. The vascular tissue is arranged in a ring.
Usually contain chlorophyll.
Woody Stems
Tissue is arranged in
layers.
 Outer bark: protects the
cells
 Inner bark: Living
phloem
 Cambium: Produces
new xylem and phloem
 Sapwood: Active xylem
 Heartwood: Old
inactive xylem.
Questions to ponder

Based on the picture and what you just learned
from woody stems,

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Which part of the stem is tapped by maple syrup
producers?
What happens to a tree trunk as it “grows”?
Where is the oldest part of a tree?
Leaves

Leaves come in all shapes and sizes. However,
the structure of leaves is adapted for capturing
the sun’s energy and carrying out
photosynthesis.
Leaf structure
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Cuticle: waxy waterproof coating
that controls water loss.
Upper leaf cells: tightly packed,
trap sunlight.
Lower leaf cells: widely spaced
allow carbon dioxide to reach
cells and oxygen to escape
Stomata: Pores on the underside
of the leaf that open and close to
allow gases to enter and exit the
leaf.
Now for applying concepts

With your table draw a three way Venn
Diagram to compare/contrast the function and
structure of leaves, stems and roots.