22.4 Flowering Plants

Key Questions

  • What are the key features of angiosperm reproduction?

  • How are different angiosperms conveniently categorized?

Vocabulary

ovary • fruit • cotyledon • monocot • dicot • woody plant • herbaceous plant

Taking Notes

Compare/Contrast Table As you read, use a table to contrast three methods commonly used to categorize angiosperms.

THINK ABOUT IT Flowering plants are everywhere. They dominate the surface of the earth and are by far the most abundant organisms in the plant kingdom. And yet they evolved much more recently than did other seed plants. What features of these plants enabled them to take Earth by storm? What are the secrets of their success?

Flowers and Fruits

What are the key features of angiosperm reproduction?

Flowering plants, or angiosperms, first appeared during the Cretaceous Period, about 135 million years ago, making their origin the most recent of all plant phyla. Flowering plants originated on land and soon came to dominate Earth's plant life. Angiosperms make up the vast majority of plant species.

Angiosperms develop unique reproductive organs known as flowers, as shown in Figure 22–18. Flowers contain ovaries, which surround and protect the seeds. The presence of an ovary gives angiosperms their name: Angiosperm means “enclosed seed.” Angiosperms reproduce sexually by means of flowers. After fertilization, ovaries within flowers develop into fruits that surround, protect, and help disperse the seeds. In Chapter 24, you will explore angiosperm reproduction in more detail.

A pictorial anatomy of a flower showing ovary and developing seed with an inset diagram of an embryo.

FIGURE 22–18 Anatomy of a Flower Within a flower, one or more ovaries develop into fruits that surround, protect, and help disperse the seeds.

End ofPage 650

Table of Contents

Miller & Levine Biology
About the Authors
Changing the World of Biology Education
Contents
Diversity of Life: A Visual Guide DOL•1–DOL•64
Labs and Activities
Features
UNIT 1 The Nature of Life
1 The Science of Biology
2 The Chemistry of Life
Unit Project
UNIT 2 Ecology
3 The Biosphere
4 Ecosystems and Communities
5 Populations
6 Humans in the Biosphere
Unit Project
UNIT 3 Cells
7 Cell Structure and Function
8 Photosynthesis
9 Cellular Respiration and Fermentation
10 Cell Growth and Division
Unit Project
UNIT 4 Genetics
11 Introduction to Genetics
12 DNA
13 RNA and Protein Synthesis
14 Human Heredity
15 Genetic Engineering
Unit Project
UNIT 5 Evolution
16 Darwin's Theory of Evolution
17 Evolution of Populations
18 Classification
19 History of Life
Unit Project
UNIT 6 From Microorganisms to Plants
20 Viruses and Prokaryotes
21 Protists and Fungi
22 Introduction to Plants
23 Plant Structure and Function
24 Plant Reproduction and Response
Unit Project
UNIT 7 Animals
25 Introduction to Animals
26 Animal Evolution and Diversity
27 Animal Systems I
28 Animal Systems II
29 Animal Behavior
Unit Project
UNIT 8 The Human Body
30 Digestive and Excretory Systems
31 Nervous System
32 Skeletal, Muscular, and Integumentary Systems
33 Circulatory and Respiratory Systems
34 Endocrine and Reproductive Systems
35 Immune System and Disease
Unit Project
A Visual Guide to The Diversity of Life
HOW TO USE THIS GUIDE
THE TREE OF LIFE
Bacteria
Protists
Fungi
Plants
Animals
Appendices
Appendix A Science Skills
Appendix B Lab Skills
Appendix C Technology & Design
Appendix D Math Skills
Appendix E Periodic Table
Glossary
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q, R
S
T
U
V
W
X, Y, Z
Index
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Credits
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