• CCB Science pages 140 - 147



  • Identify basic characteristics of microbes

  • Recognize different types of microbes

  • Understand the role of microbes in the environment

Key Concept

  • Single-celled organisms, including bacteria and protists, are the simplest of all organisms. Along with viruses, they are both helpful and harmful to other living things.


Tier 2 compare
Tier 3 decomposer

Evidence-Based Reading

  • Echo Reading: Provide a model of expressive, fluent reading by conducting an echo read of the text on this page. Begin by reading the heading and first sentence aloud, and then ask the class to repeat after you. Take care to pronounce unfamiliar words clearly and repeat sentences as needed. Gradually increase your reading speed to encourage students to identify words more quickly.

21st Century Skill

  • Productivity and Accountability: Ask students to distinguish between productivity and accountability. Point out that accountability means that a person is publicly responsible for something they have done. Ask students to describe the connection between accountability and personal reputation.

Writing Practice

  • As students plan their compare-and-contrast paragraphs, discuss alternate organizational structures for their writing. They could list all the relevant characteristics of the first item and then write about how the characteristics of the other item are the same or different, or they could compare and contrast each aspect of the items, one after the other.

Before Lesson

Find out how much students know about the microbes that are a part of their daily lives. Students may think of microbes only as germs or agents of disease. Explain to students that microbes can be both beneficial and harmful. Ask students if they are familiar with any food items that are made using microbes; for example, some students may know that yogurt, cheese, and bread are made using microbes. Tell students that this lesson may surprise them as to just how many microbes are all around, inside and out of their bodies.


All living things are made up of cells. Some organisms, such as amoeba, are made up of just one cell, whereas a human being has anywhere from SO to 100 trillion cells. Although single-celled organisms are called simple, they have played a huge part in developing life on Earth. As students read, help them take notes on the various kinds of microbes that are found in their environment- internally as well as externally.

Guided Practice

  • Simple Organisms
    • Microbes
    • Archaea
    • Eukarya
    • Viruses
  • Multicellular Organisms
    • Fungi
    • Algae
    • Mosses
    • Ferns

Core Skill

Compare and Contrast Information: Draw a Venn diagram on the board and have the class fill it in as a group. After finishing the activity, discuss with students why a Venn diagram is such a helpful graphic organizer for comparing and contrasting information. Have students consider how other graphic organizers could also be used to compare and contrast viruses and other microbes.

Cite Textual Evidence: After reviewing the sidebar activity with students, ask them to consider how the other forms of fungi cited in the text-mold, mildew, and yeast- also thrive in moist environments. Encourage student volunteers to tell you where they’ve seen mold and mildew before, such as in damp outdoor environments.


Main Idea and Details: Show students how to organize details using the Main Idea graphic organizer found in the Graphic Organizer section of the Instructor Resource Binder. Have students use this graphic organizer to summarize the key characteristics of the different kinds of simple organisms described in this lesson. Explain to students how they can add important details to the Detail boxes descending from each Main Idea bar.

Organize, Represent, and Compare: Data Have students research the impact of each group of organisms on humans. Ask students to organize the groups archaea, bacteria, eukarya, viruses, fungi, algae, mosses, and ferns in a graphic organizer and compare how they are helpful or harmful to humans. For each group, challenge students to draw a conclusion based on the evidence.

Lesson Review