Cell Division and Growth

Overview

In this 60-minute lesson, students use physical and visual models to explain how cytokinesis differs in plant and animal cells. They connect cell division with growth, tissue repair and stem cells, then evaluate how uncontrolled division can lead to cancer. This lesson builds on prior learning about cell structures, the cell cycle and mitosis.

Learning intentions

Students will:

• explain the purpose of cytokinesis following nuclear division
• model and compare cytokinesis in plant and animal cells
• relate cell division to growth, tissue repair and stem cells
• describe how uncontrolled cell division can affect an organism

Success criteria

• I can explain how cytokinesis produces two separate daughter cells.
• I can identify and explain one difference between cytokinesis in plant and animal cells.
• I can link controlled cell division to growth, repair or stem cells.
• I can describe why uncontrolled cell division is harmful.

Curriculum links

• Students explain how cell structures enable biological processes needed for life, including cell division.
• Students explain how cells contribute to complex multicellular organisms through growth and tissue repair.
• Students identify the functions of cell structures involved in division, including the nucleus, cell membrane and cell wall.

Lesson structure (60 minutes)

1. 0–7 min · Hook and retrieval. Open with the hook and retrieval slides showing two identical cells becoming four, followed by the question, “How can one cell become two cells without losing the information needed for life?” Students complete a brief think-pair-share and answer three retrieval questions about DNA, chromosomes and mitosis in their books.

2. 7–17 min · Explicit teaching. Use the cytokinesis teaching slides to review that mitosis separates duplicated chromosomes, while cytokinesis divides the cytoplasm and cell boundaries. Model animal-cell cytokinesis as a cleavage furrow formed when the cell membrane constricts, and plant-cell cytokinesis as a cell plate forming between the daughter nuclei before developing into a new cell wall. Students annotate a simple comparison diagram on the cytokinesis comparison worksheet.

3. 17–32 min · Group modelling task. Arrange 35 students into groups of five and provide modelling materials such as modelling clay, string or paper circles. Display the model-building instruction slide. Each group creates a sequence showing cytokinesis in either an animal or plant cell, including the daughter nuclei, cytoplasm, cell membrane and, where relevant, the cell plate and cell wall. Students label the model and prepare a 45-second explanation using the sentence frame: “Cytokinesis in a ___ cell occurs when ___, because ___.”

4. 32–42 min · Compare and critique. Use the compare-and-critique slides to organise a gallery walk. Students view models from both cell types and record one similarity and two differences on the worksheet. They must identify how the presence of a rigid cell wall affects cytokinesis in plant cells. The teacher checks explanations and corrects the common misconception that cytokinesis and mitosis are the same process.

5. 42–52 min · Applications: growth, repair and stem cells. Present three short scenarios on the applications slides: a growing adolescent, skin healing after a cut and a stem cell producing specialised blood cells. In pairs, students complete the application questions on the worksheet, identifying where cell division occurs and explaining how producing new cells supports the organism. Discuss that stem cells can divide and may differentiate into specialised cell types, depending on signals and tissue needs.

6. 52–57 min · Uncontrolled division. Show the controlled-versus-uncontrolled-division slide. Students interpret a simple visual comparison of regulated cell division and a growing mass of abnormal cells. They write a two-sentence explanation: “Normal cell division is controlled by ___. Uncontrolled division may result in ___.” Emphasise that cancer involves abnormal cell division and that not every tumour behaves in the same way.

7. 57–60 min · Exit check. Finish with the plenary and exit-question slide. Students answer: “Explain one structural difference between plant and animal cytokinesis and connect it to one biological function of cell division.” Collect responses as the exit ticket and identify students needing follow-up before the next lesson.

Resources

• the cell division and growth slide deck
• the cytokinesis comparison worksheet
• Modelling clay, string, paper circles or reusable cell-model materials
• A3 paper and coloured markers
• Projector or interactive display
• Student books and pens
• Timer
• Board or visualiser for displaying group models

Assessment

• During retrieval and explicit teaching, question students about the distinction between mitosis and cytokinesis.
• Use group models, labelled diagrams and gallery-walk explanations to assess understanding of plant and animal cytokinesis.
• Review the exit response for accurate use of cell structures, controlled division and applications to growth, repair or stem cells.

Differentiation

• Provide a partially labelled diagram, a word bank and sentence starters on the worksheet for students requiring support: “The cell plate forms because…” and “Both types of cytokinesis…”.
• Allocate mixed-ability groups and assign clear roles: materials manager, model builder, label writer, speaker and scientific checker.
• Support EAL students with diagrams, explicit pronunciation of key terms and paired rehearsal before presenting.
• Extend confident students by asking them to explain how failure of cell-cycle checkpoints could contribute to uncontrolled division, while distinguishing correlation from a complete explanation of cancer.