| Lesson Plan |
| Grade: |
Date: 25/02/2026 |
| Subject: Biology |
| Lesson Topic: describe the distribution of xylem and phloem in transverse sections of stems, roots and leaves of herbaceous dicotyledonous plants |
Learning Objective/s:
- Describe the arrangement of xylem and phloem in transverse sections of herbaceous dicot stems, roots, and leaves.
- Compare the positional differences of vascular tissues among stem, root, and leaf cross‑sections.
- Identify key associated tissues (cambium, cortex, pith, pericycle, mesophyll) and explain their relationship to transport tissues.
- Interpret labelled diagrams to locate xylem and phloem in each organ.
- Apply knowledge to predict how changes in tissue arrangement affect water and nutrient transport.
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Materials Needed:
- Projector or interactive whiteboard
- PowerPoint/slide set with labelled diagrams of stem, root, and leaf sections
- Handout with blank transverse‑section diagrams for labeling
- Microscopy images or prepared slides of dicot stem, root, and leaf
- Coloured pencils or markers for student labeling
- Whiteboard and markers
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Introduction:
Begin with a quick image of a plant cross‑section and ask students where water and food travel inside the plant. Recall previous learning about xylem and phloem functions. Explain that today they will discover how these tissues are positioned differently in stems, roots and leaves, and that success will be demonstrated by accurately labeling diagrams.
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Lesson Structure:
- Do‑now (5') – Students sketch a simple plant and list known functions of xylem and phloem.
- Mini‑lecture (10') – Present the three organ cross‑sections, highlighting the ring of vascular bundles in stems, central stele in roots, and collateral bundles in leaves.
- Guided analysis (15') – In pairs, students label printed diagrams using coloured pencils; teacher circulates, prompting identification of xylem vs phloem and associated tissues.
- Think‑pair‑share (5') – Groups compare their labelled diagrams and discuss why xylem is always interior to phloem.
- Formative check (5') – Kahoot/quiz questions on tissue positions.
- Extension activity (10') – Students draw a simplified transverse section of a dicot organ not covered (e.g., a flower pedicel) and predict xylem/phloem arrangement.
- Summary & reflection (5') – Whole‑class recap of key patterns.
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Conclusion:
Summarise that in dicot stems xylem lies toward the centre of each bundle, in roots it is central within the stele, and in leaves it faces the adaxial side. Ask each student to write one sentence on an exit ticket describing a tissue arrangement they found most surprising. For homework, assign a worksheet requiring labelling of additional cross‑sections and a short paragraph on how tissue layout influences transport efficiency.
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