Lesson Plan

• Describe water potential and its components (solute, pressure, gravitational, matric).
• Explain the step‑by‑step process of transpiration pull using the cohesion‑tension theory.
• Analyse how environmental factors influence the rate of transpiration.
• Identify common misconceptions about plant water transport and correct them.

• Projector and screen
• PowerPoint/Google Slides presentation with diagrams
• Handout summarising the steps of transpiration pull
• Prepared leaf and stem cross‑section diagrams (printed or on board)
• Worksheet with short questions and a misconception‑matching activity
• Whiteboard and markers

Begin with a striking image of a wilted plant and ask students why water movement is essential for plant survival. Recall previous lessons on osmosis and diffusion as foundational concepts. State that by the end of the lesson they will be able to describe how evaporation at the leaf surface creates a pull that moves water from roots to leaves.

1. Do‑Now (5'): Quick quiz on water potential terms displayed on the board.
2. Mini‑lecture (10'): Present the cohesion‑tension theory with annotated diagrams.
3. Guided Walkthrough (12'): Step‑by‑step explanation of the six stages of transpiration pull, using the leaf‑stem diagrams.
4. Interactive Activity (10'): Students work in pairs to match factors (temperature, humidity, etc.) with their effects on transpiration rate.
5. Misconception Check (8'): Whole‑class discussion correcting the three common myths listed in the notes.
6. Formative Check (5'): Exit ticket – one sentence summarising how water moves up the plant.

Recap the key idea that evaporation creates a negative water potential that, together with cohesion and adhesion, pulls water upward. Collect exit tickets to gauge understanding and assign a short homework: label a diagram of a plant showing the direction of water movement and list two factors that could reduce transpiration.