A Cladogram of Plant Groups
– shows evolutionary relationships of plants
Cone-bearing
plants
Ferns and
their relatives
Flowers; Seeds
Enclosed in Fruit
Mosses and
their relatives
Seeds
Water-Conducting
(Vascular) Tissue
Green algae
ancestor
Flowering
plants
The Diversity of Plants
Cone-bearing plants
760 species
Ferns and
their relatives
11,000 species
Mosses and
their relatives
15,600 species
Flowering
plants
235,000 species
Structure of a Leaf
- the cuticle protects the leaf against transpiration
Cuticle
Veins
Epidermis
Palisade
mesophyll
Xylem
Phloem
Spongy
mesophyll
Epidermis
Stoma
Guard
cells
Vein
Plants
are categorized as
Annuals
Biennials
Perennials
that complete
their life cycle in
that complete
their life cycle in
that complete
their life cycle in
1 growing
season
2 years
More than
2 years
Types of Plants – Seedless
• Mosses (Bryophytes)
• Ferns (Pterophyta)
Types of Plants - seeds
• Cone Bearing (Gymnosperms)
• Flowering (Angiosperm)
Gymnosperms vs Angiosperms
Comparing Features of Seed Plants
Feature
Gymnosperms
Angiosperms
Seeds
Bear their seeds on cones
Bear their seeds within
flowers
Reproduction
Can reproduce without water;
male gametophytes are
contained in pollen grains;
fertilization occurs by
pollination
Can reproduce without water;
male gametophytes are
contained in pollen grains;
fertilization occurs by
pollination
Examples
Conifers, cycads, ginkgoes,
gnetophytes
Grasses, flowering trees and
shrubs, wildflowers, cultivated
flowers
Flower Functions
• Sexual Reproduction!
• Flowers are pollinated by:
– Wind
– Insects
– Birds
FLOWER PARTS
• Pistil – female part of the plant
– Contains the stigma, style and ovary (surround and protect
the seeds)
FLOWER PARTS
• Stamen – male part of the plant
– Contains the anther and filament
FLOWER PARTS
• Petals – colorful, leaflike structures
• Sepals – green leaflike structures at the base of the
flower
The structure of a flower.
Stamen
Anther
Filament
Ovule
Carpel
Stigma
Style
Ovary
Petal
Sepal
Fruit
– after pollination the ovary develops a
wall of tissue surrounding the seed
Figure 22–25
Comparison of
Monocots and Dicots
Comparison of Monocots and Dicots
Monocots
Dicots
Seeds
Single
cotyledon
Two
cotyledons
Leaves
Parallel
veins
Branched
veins
Flowers
Floral parts
often in
multiples of 3
Floral parts often in
multiples
of 4 or 5
Stems
Vascular
bundles
scattered
throughout stem
Vascular
bundles
arranged in
a ring
Roots
Fibrous roots
Taproot
Transpiration
A
B
Evaporation of water
molecules out of leaves.
Pull of water molecules upward
from the roots.