CCB Science pages 70 - 77
Relate fermentation to energy
Relate the absence of oxygen to fermentation
Explain the process of fermentation
Fermentation is a process that produces energy within a cell in the absence of oxygen.
Model Fluent Reading: Remind students that each punctuation mark in a text serves a purpose. Review the first paragraph on page 70 as a class, asking students to identify the places where commas appear. Ask students what those commas tell a reader to do. Then ask students to listen as you read the paragraph aloud, first reading while ignoring the commas and then reading while acknowledging the commas. Afterward, ask students to describe the differences in what they heard. Invite volunteers to read the paragraph again, modeling fluent reading.
21st Century Skill
Productivity and Accountability: Write the words productivity and accountability on the board or on a chart. Ask students to explain what they think each word means. Guide their responses to help them understand that productivity is the effective use of time and resources to produce a result, and accountability is personal responsibility for making something happen. Encourage students to give examples of times they have been both productive and accountable. Then have them read the text and explain how their behaviors are similar to the behaviors of scientists.
Remind students to read carefully before beginning to write. Encourage them to think in terms of their own experiences as they write.
In this lesson students will learn about the process of fermentation as a means of breaking the bonds of sugar molecules to harvest the energy of those bonds in the absence of oxygen. To determine their readiness for the lesson, invite students to discuss their experiences baking or observing the preparation of yeast breads, such as loaf bread, rolls, and doughnuts. Or bring in a loaf of bread, and ask students to observe the bread’s texture. Ask students to predict what might cause the holes they see to form.
Explain to students that cellular fermentation is similar to cellular respiration, in that cells use the process to harvest the energy locked in the chemical bonds of sugar molecules. However, cellular respiration occurs in the presence of oxygen, so it is aerobic. Fermentation occurs in the absence of oxygen, so it is anaerobic. Ask students when they have heard or read the terms aerobic before. Prompt them, if necessary, to think of aerobic exercise, and that such exercise requires more oxygen intake. Then explain that the prefix an- means “without.” Ask a volunteer to define the term anaerobic
- Ethanol: An Alternative Energy Source
Apply Scientific Processes: Invite students to discuss professionals who conduct investigations, collect data, or information, and form hypotheses, or conclusions based on that data. Students may say, for example, that police officials conduct investigations to gather data and come to some conclusions about specific crimes. Companies hire chemists and engineers to collect data on new products to be sure they are safe for consumers. Help students understand that no matter the purpose of their work, these professionals follow similar procedures to be sure their conclusions are valid. Read the text in the ## Core Skill with students. Then organize students into small groups, and have each group draw and label the steps in the scientific process. Encourage students to share their work.
Compare and Contrast Information: After students have completed the investigation, ask them to use print, online, or other resources to find a similar experiment to observe the process of fermentation. Invite volunteers to describe similarities and differences between the investigation they conducted and the investigations they found. Ask students to consider the similarities and differences to offer suggestions for improving the investigation they conducted.
Explain a Diagram: Gather students into small groups. Encourage them to recall the “Blow Up a Balloon” experiment. Ask students to use their own words to explain why the balloon inflated. Invite students to write simple sentences or draw illustrations to support their explanations.
Write an Explanation of a Process: Encourage students to learn more about yeast, a microscopic fungus that reproduces rapidly in certain conditions. Have them work in pairs, small groups, or independently to learn how yeast are manufactured for use in baking. Ask students to collaborate to write an explanation for how yeast work in the baking process.