Materials

  • CCB Science pages 62 - 69

Standards

Objectives

  • Relate respiration to energy

  • Identify step-by-step scientific procedures

  • Describe the role of oxygen in the process of respiration

  • Explain the process of cellular respiration

Key Concept

  • When you breathe, you respire, or bring oxygen into your body. This process is called respiration. There’s another kind of respiration, too. Within your cells, microscopic structures use the oxygen that you respire to release the energy locked in food molecules.

Vocabulary

Tier 2 aerobic
initiative
procedure
process
Tier 3 cellular respiration
glycolysis
mitochondria

Evidence-Based Reading

  • Word Parts: Write the word carbohydrate on the board. Explain that the word comes from two word parts: carbo + hydrate. Also explain that the word part carbo comes from the chemical element carbon, and the word part hydro comes from the Greek word hydor, meaning ‘water’. Remind students that the chemical structure of water is H_2O, or two hydrogen atoms bonded to one oxygen atom. Explain that all carbohydrates, from simple sugars to starches, are a combination of carbon, hydrogen, and oxygen atoms. Show or project models of the chemical structures of a variety of carbohydrates and invite students to identify the carbon, hydrogen, and oxygen atoms in each structure.

21st Century Skill

  • Initiative and Self-Direction: Have students read the text and then explain initiative and self-direction in their own words. Invite students to give specific examples of personal initiative and explain that the result or effect of that initiative. Ask students to offer opinions on why such behaviors might be particularly helpful in the workplace.

Writing Practice

  • Remind students to think through the process of the experiment before attempting to write. Then have them order and number the steps. If possible, have students compare their steps with a partner to determine if all necessary steps are included and ordered properly.

Before Lesson

This lesson requires students to be familiar with the process of respiration in living organisms. Students learn that oxygen is required for cellular respiration, and carbon dioxide is given off as a waste product. Ask students to describe how their bodies responded to a period of heavy exercise or rigorous sport. Prompt students to explain how their activities affected their breathing rates. Explain that these experiences are connected to what they will learn about in this lesson.

Background

Explain to students that respiration, or breathing, has two parts-inhalation and exhalation. Tell them that during inhalation, they breathe in oxygen, which leaves the lungs and enters the bloodstream, where it is delivered to the body’s cells. The cells use it to break down sugar molecules to produce high-energy ATP molecules. The process releases carbon dioxide as a waste gas. Relate this process to students’ descriptions of how their breathing changed during heavy exercise or sport. Invite a volunteer to draw a simple diagram on the board to represent the gas exchange that occurs during rest and during activity.

Guided Practice

  • The Need for Energy
  • Mitochondria
  • Inside the Cell
  • Bioremediation

Core Skill

Determine Meaning of Terms: Read the explanation aloud and as a class use the word parts to define each term. Encourage students to construct and share sentences that use the words.

Follow a Multistep Procedure: Review the steps in the procedure for examining microorganisms in pond water. If possible, have students use tools and samples of pond water to complete the procedure. Discuss the value of writing numbered steps. Help students understand the value of writing explicit instructions for a scientific investigation. (Steps make the investigation reproducible, meaning results should be similar.)

Extension

Explain a Diagram: Gather students into small groups. Encourage them to examine the close up of a mitochondrion in the diagram on page 64 and explain cellular respiration in their own words. Students may want to number the steps they describe, either orally or on paper, as they explain.

Interpret a Multistep Process: Organize students into small groups and provide drawing materials. Have students write the steps for a familiar process, such as repairing a bicycle or changing an automobile tire. Have students draw diagrams to support the directions in each step.

Lesson Review