20.2 Classification of Plants.ppt

1. 20.2 Classification of Plants
KEY CONCEPT
Plants can be classified into nine phyla/divisions.

2. 20.2 Classification of Plants
Land plants are classified by the presence or absence of
vascular tissue and how they reproduce (with or without
seeds)
• “Vascular”
– People: relating to vessels, especially those that
carry blood.
– Plants: relating to plant tissues that conduct water,
sap, and nutrients.

3. 20.2 Classification of Plants
Vascular Plants vs. Nonvascular Plants
Vascular
• Transport System
– Leaves
– True roots
– Xylem
– Phloem
– Stems
• Can grow tall
• Live in dry areas
Nonvascular
• No Transport System
– No roots (rhizoids)
• Grow close to the
ground to absorb water
and nutrients
• Live in moist areas
*Complete Venn Diagram in notes

4. 20.2 Classification of Plants

5. 20.2 Classification of Plants
Nonvascular Plants

6. 20.2 Classification of Plants
Mosses and their relatives are seedless nonvascular
plants.
• Liverworts belong to phylum Hepatophyta.
– often grow on wet rocks or in greenhouses
– can be thallose or leafy

7. 20.2 Classification of Plants
• Mosses belong to phylum Bryophyta.
– most common seedless nonvascular plants
– sphagnum moss commonly used by humans as “peat”

8. 20.2 Classification of Plants
• Hornworts belong to phylum Anthocerophyta.
– found in tropical forests and along streams
– flat, lobed body with little green “horns”

9. 20.2 Classification of Plants
Vascular Plants
Seedless vs. w/Seeds

10. 20.2 Classification of Plants
Club mosses and ferns are seedless vascular plants.
• Club mosses belong to phylum Lycophyta.
– not true mosses
– oldest living group of vascular plants

11. 20.2 Classification of Plants
• Ferns and their relatives belong to phylum Pterophyta.
frond
fiddlehead
– whisk ferns and horsetails are close relatives of ferns
– ferns have large leaves called fronds

12. 20.2 Classification of Plants
Seed plants include cone-bearing plants and flowering
plants.
• Seed plants have several advantages over their seedless
ancestors.
– can reproduce without free-standing water, via
pollination
– seeds nourish and protect plant embryo
– seeds allow plants to disperse to new places

13. 20.2 Classification of Plants
• Gymnosperms do not have seeds enclosed in fruit.
– most gymnosperms are cone-bearing.
– the cone is reproductive structure of most gymnosperms.
– pollen is produced in male cones.
– eggs are produced in female cones.
– seeds develop on scales of female cones.

14. 20.2 Classification of Plants
• Cycads are gymnosperms in phylum Cycadophyta.
– look like palm trees with large cones
– grow in tropical areas

15. 20.2 Classification of Plants
• Ginkgos are gymnosperms in phylum Ginkgophyta.
– only one species alive today, Ginkgo biloba
– grown in gardens and used in urban landscaping

16. 20.2 Classification of Plants
• Conifers are gymnosperms in phylum Coniferophyta.
– most common
gymnosperms alive
today
– includes pines, spruce,
cedar, fir, and juniper

17. 20.2 Classification of Plants
• Angiosperms have seeds enclosed in some type of fruit.
– A flower is the reproductive structure of angiosperms.
– A fruit is a mature ovary of a flower.
• Angiosperms, or flowering plants, belong in phylum Anthophyta.

18. 20.2 Classification of Plants
Plant Classification Lab
• Goal: Identify plants as either vascular or nonvascular
based on microscope analysis.
• This lab does not need to be a formal write up… only
include the Title, Goal, and components listed below:
– Draw image and label transport system
components
– Record slide name and number
– Record as either vascular or nonvascular