Quick Lab
GUIDED INQUIRY

What Are Protists?

  1. Place a drop of water containing a variety of microorganisms on a microscope slide. Add a drop of methyl cellulose and a coverslip. Observe the slide under the microscope at low and high magnifications.

  2. Record your observations by drawing and labeling each type of organism.

  3. Make a chart listing each type of organism you observed and its characteristics.

    Analyze and Conclude

  1. Observe For any of the organisms that move, describe their motion and any structures involved in producing the motion.

  2. Draw Conclusions Do you observe any structures that you think relate to food-gathering or reproduction? Explain why you think so.

  3. Classify Are any of these organisms bacteria, plants, or animals? Explain your answer.

The “Protist” Dilemma In recent years, biologists have studied these eukaryotes closely, eager to learn what the organisms reveal about the history of life. They have discovered that the “protists” display a far greater degree of diversity than any other eukaryotic kingdom. Furthermore, they found that many of these organisms are far more closely related to members of other eukaryotic kingdoms than they are to other “protists.”

This finding has created a dilemma. By definition, the members of a living kingdom, such as plants or animals, should be more like one another than like members of other kingdoms. This is not true of protists, which means that reclassification is necessary. Biologists continue to debate the best way to do this.

In the past, scientists sorted protists into three groups: plantlike protists, animal-like protists, and funguslike protists. This simple solution began to fail as biologists learned that many protists do not fit into any of these groups. To make matters worse, they discovered that many of the animal-like and funguslike protists are so similar that they belong in a single group, not split into two. Clearly, a new way of thinking about the “protists” is now needed.

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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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