Five Kingdoms As researchers began to study microorganisms, they discovered that single-celled organisms were significantly different from plants and animals. At first all microorganisms were placed in their own kingdom, named Protista. Then yeasts and molds, along with mushrooms, were placed in their own kingdom, Fungi.

Later still, scientists realized that bacteria lack the nuclei, mitochondria, and chloroplasts found in other forms of life. All prokaryotes (bacteria) were placed in yet another new kingdom, Monera. Single-celled eukaryotic organisms remained in the kingdom Protista. This process produced five kingdoms: Monera, Protista, Fungi, Plantae, and Animalia.

Analyzing Data

Comparing the Domains

The table in Figure 18–14 compares the three domains and six kingdoms. Use the information in the table to answer the following questions.

  1. Interpret Tables Which kingdom has cells that lack cell walls?

  2. Interpret Tables Which domain contains multicellular organisms?

  3. Compare and Contrast On the basis of information in the table, how are the members of domain Archaea similar to those of domain Bacteria? How are organisms in domain Archaea similar to those in domain Eukarya?

Six Kingdoms By the 1990s, researchers had learned a great deal about the genetics and biochemistry of bacteria. That knowledge made clear that the organisms in kingdom Monera were actually two genetically and biochemically different groups. As a result, the monerans were separated into two kingdoms, Eubacteria and Archaebacteria, bringing the total number of kingdoms to six. The six-kingdom system of classification includes the kingdoms Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia. This system of classification is shown in the bottom row of Figure 18–13 on the previous page.

A table shows "Classification of Living Things" are grouped into three domains.

FIGURE 18–14 Three Domains Today organisms are grouped into three domains and six kingdoms. This table summarizes the key characteristics used to classify organisms into these major taxonomic groups.

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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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