Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Biology
Lesson Topic: State that water is absorbed by root hair cells.
Learning Objective/s:
  • Describe the role of root hairs in water uptake.
  • Explain how osmosis drives water movement into root hair cells.
  • Identify the pathway of water from root hairs to the xylem, including the function of the Casparian strip.
  • Analyze factors that affect the rate of water absorption in plants.
  • Correct common misconceptions about water uptake in roots.
Materials Needed:
  • Projector and screen for diagram presentation
  • Whiteboard and markers
  • Handout with root cross‑section diagram
  • Microscopy slides of root hair cells (optional)
  • Worksheet with short‑answer and labeling tasks
  • Beaker of water and potato slices for a simple osmosis demonstration
 Introduction:
Begin with a short video of a wilting plant that recovers, prompting students to consider how plants obtain water. Review prior learning on cell membranes and diffusion, then state that today they will investigate how root hairs absorb water. Explain that success will be measured by their ability to diagram the water‑uptake pathway and answer key questions.
Lesson Structure:
  1. Do‑now (5'): Students write on sticky notes where a plant gets its water.
  2. Mini‑lecture (10'): Present root hair anatomy and the concept of osmosis using slides.
  3. Guided activity (12'): Label a cross‑section diagram of a root, highlighting apoplast, symplast, Casparian strip, and xylem.
  4. Demonstration (8'): Simple osmosis demo with potato slices in a salt solution; discuss observations.
  5. Group discussion (10'): Answer check‑understanding questions about root hairs, the Casparian strip, and water‑potential direction.
  6. Exit ticket quiz (5'): Write one sentence stating how water moves from soil into the xylem.
Conclusion:
Recap that water enters root hairs by osmosis, travels through the cortex, and reaches the xylem after crossing the Casparian strip. Students write one key fact on a post‑it as an exit ticket. For homework, ask them to research how environmental factors such as soil moisture influence root water uptake.