Leaf Classification

1. Focus Question: How can
leaves be classified?
Living Systems 2-2

2. Focus on Leaves
Vascular plants are composed of
millions of living cells
Every cell needs water, minerals,
and food (sugar)
Vascular system of plants is really
two systems
Xylem transports water and minerals
to the cells
Phloem transports sugar to the cells

3. Most xylem tubes begin in the
roots and end in the leaves.
Most phloem tubes start in the
leaves and end in the roots.
Find out about the place where the
xylem ends and the phloem
begins, the leaf.

4. Leaf Collection
Stay with your group
Collect ONE leaf from as many
different plants as you can find in
5 minutes. Get leaves of all sizes.
Keep sample in the bag.

5. Sorting Leaves
Look closely at each leaf
Sort into those that show evidence
of xylem and phloem and those
that don’t.
How many of your leaves have
veins?
Are the veins all the same size?
Do the veins branch?
Sort your leaves in a new way.

6. Classification
Scientists organize, or classify, things
so they can think about them more
efficiently
A group of things that go together based
on a property or behavior is a class.
5th
graders form a class based on age. 4th
graders are a different class, etc… In
schools we classify students by age.
 Geology – classify crystals by shapes and
angles of surfaces. Classify sand by
particle size.

7. Leaf Classification
Based on basic pattern of the
veins.
Botanists have developed a
systems that uses three patterns.
Palmate
Pinnate
Parallel

8. Palmate
 Several large veins
extending from the
place where the leaf
stem attaches to the
leaf.
 Think of the palm of
your hand and your
fingers as the main
veins.

9. Pinnate
 One large vein
extending the
length of the leaf
with smaller veins
branching off.
 Pinna means
feather, so a
pinnate leaf
resembles a
feather

10. Parallel
 Many small veins
running the
length of the leaf.
 Long, narrow
leaves, like blades
of grass, tend to
have parallel
veins.

11. Leaf Classification
Classify your leaves based on
venation pattern.
Are there other ways to classify
your leaf collections?
Leaf Shape (Blade)
Kind of edge (Margin)
Kind of attachment (Petiole)

12. Vocabulary
 Classify
 To organize by similar properties or
behavior
 Palmate
 Several large veins extending from the
place where the leaf stem attaches to the
leaf (Palm)
 Pinnate
 One large vein extending the length of the
leaf with smaller veins branching off
(Feather)
 Parallel
 Many small veins running the length of the
leaf (Grass)

13. Content
Venation
Classifying leaves by their vein
pattern
How do scientists organize objects
and information?
Scientists classify things by
putting them in groups (classes)
based on similar properties and
behaviors.

14. Homework
Read Classification, pg. 105-106,
and Summary: Vascular Plants,
pg. 107-109
Answer questions for both articles
I-check 2 quiz on Friday, 1/23

15. Classification
What is classification?
What are three different ways leaves
can be classified?
If you had a collection of insects, what
ways might you classify them?

16. Summary: Vascular Plants
Describe how all the cells in a vascular
plant get sugar.
Describe how all the cells in a vascular
plant get water and minerals.
Why do its leaves turn pink when a
celery stalk is placed in red water?
In what way are blood and sap the
same?

17. Name That Leaf
 Palmate Leaf

18. Name That Leaf
 Parallel Leaf

19. Name That Leaf
 Pinnate Leaf

20. Could These Leaves Come
From the Same Plant?
 Why?

21. Could These Leaves Come
From the Same Plant?
 Why?