UNIT 6 From Microorganisms to Plants 571–726
20 Viruses and Prokaryotes 572
Are all microbes that make us sick made of living cells?
20.1 Viruses 574
20.2 Prokaryotes 580
20.3 Diseases Caused by Bacteria and Viruses 586
The Mad Cows
21 Protists and Fungi 600
How do protists and fungi affect the homeostasis of other organisms and ecosystems?
21.1 Protist Classification—The Saga Continues 602
21.2 Protist Structure and Function 606
21.3 The Ecology of Protists 610
21.4 Fungi 618
”A Blight of Unusual Character”
22 Introduction to Plants 632
What are the five main groups of plants, and how have four of these groups adapted to life on land?
22.1 What Is a Plant? 634
22.2 Seedless Plants 639
22.3 Seed Plants 646
22.4 Flowering Plants 650
Stone Age Storytellers
23 Plant Structure and Function 662
How are cells, tissues, and organs organized into systems that carry out the basic functions of a seed plant?
23.1 Specialized Tissues in Plants 664
23.2 Roots 669
23.3 Stems 674
23.4 Leaves 680
23.5 Transport in Plants 685
The Hollow Tree