Respiratory System I (Lesson note)

DETAILED LESSON NOTE
Class: JSS 2 (Grade 8)
Subject: Basic Science
Topic: Respiratory System I
Duration: 40 minutes

Week: Eight
Date: To be inserted by teacher
Average Age: 12–14 years

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Instructional Objectives

By the end of the lesson, students should be able to:

1. Define the respiratory system correctly. (Lower domain – Knowledge)
2. Explain respiration and distinguish between aerobic and anaerobic respiration with one example each. (Middle domain – Understanding/Application)
3. Draw and label the human respiratory system correctly, identifying at least four major parts. (Higher domain – Analysis)

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Instructional Materials

• Chart/diagram of the human respiratory system
• Whiteboard and marker
• Drawing sheet / graph sheet
• Textbook

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Entry Behaviour

Students already know that humans breathe in oxygen and breathe out carbon dioxide daily.

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Lesson Development

Step I: Introduction (5 minutes)

• Teacher greets students and asks:
  “What happens if someone stops breathing for a long time?”
• Expected responses: “They can faint”, “They can die”, “They will be weak”.
• Teacher explains that breathing and energy release are controlled by a body system known as the respiratory system.

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Step II: Presentation (25 minutes)

Objective 1: Meaning of Respiratory System (5 minutes)

• Teacher explains: The respiratory system is the body system that helps living things take in oxygen and release carbon dioxide.
• Teacher links this to daily life: “Each time you breathe in air through your nose, you are using your respiratory system.”
• Students repeat the definition and give simple examples of breathing.

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Objective 2: Respiration and Its Types (10 minutes)

• Teacher explains respiration: the process by which food substances are broken down to release energy in the body.
• Teacher divides respiration into two types:

1. Aerobic Respiration (with oxygen)
• Equation: Glucose + Oxygen → Carbon dioxide + Water + Energy
• Example: Normal breathing when jogging lightly.
• Produces much energy.
2. Anaerobic Respiration (without oxygen)
• Equation (in humans): Glucose → Lactic acid + Small energy
• Equation (in yeast): Glucose → Alcohol + Carbon dioxide + Small energy
• Produces less energy and causes muscle cramps.

• Teacher asks students to compare:
• Oxygen used or not used?
• Energy: large or small?
• By-products?
• Students provide answers in pairs, and teacher reinforces correct ones.

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Objective 3: Diagram of Human Respiratory System (10 minutes)

• Teacher displays a chart of the human respiratory system.
• Teacher identifies and explains major parts:
• Nose: where air enters
• Trachea (windpipe): passage of air to lungs
• Bronchi: branches of the trachea
• Lungs: organs of gas exchange
• Diaphragm: muscle that helps breathing in and out
• Teacher guides students to draw the diagram in their notebooks.
• Students label at least 4 parts correctly.
• Teacher moves around, checks, and corrects their work.

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Step III: Conclusion (5 minutes)

• Teacher revises key points:
• Meaning of respiratory system
• Respiration and its two types
• Diagram of human respiratory system and its parts
• Teacher asks students to repeat after him/her for reinforcement.

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Evaluation (5 minutes)

Teacher asks students:

1. What is the respiratory system?
2. Differentiate between aerobic and anaerobic respiration.
3. Draw and label four parts of the human respiratory system.

(Students respond orally and in their notebooks)

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Assignment

• Write three differences between aerobic and anaerobic respiration in your notebook.
• Draw the human respiratory system neatly and label five parts.