Mitosis Stage by Stage

Overview

In lesson 20 of the 30-lesson unit Cells: The Basis of Life, students consolidate their understanding of cell division by identifying the stages of mitosis in diagrams and microscope images. They use chromosome behaviour to explain how one parent cell produces two genetically identical daughter cells, building on prior learning about cell structures and the cell cycle.

Learning intentions

Students will:

• Identify prophase, metaphase, anaphase and telophase in diagrams and images.
• Describe the observable chromosome behaviour in each stage.
• Explain how chromosome copying and separation produce genetically identical daughter cells.
• Distinguish mitosis from cytokinesis and sequence the stages accurately.

Success criteria

• I can identify the four stages of mitosis from visual evidence.
• I can describe what chromosomes, the spindle and nucleus are doing at each stage.
• I can explain why each daughter cell receives an identical set of chromosomes.
• I can correctly sequence stages and justify my decisions using biological evidence.

Curriculum links

• Cells as the basis of life: cell structures and functions, biochemical processes and cell division.
• Students explain how cell structures enable biological processes needed for life.
• The lesson supports understanding of how cells contribute to the growth, repair and maintenance of multicellular organisms.

Lesson structure (60 minutes)

1. 0–5 min · Hook and retrieval. Open with the chromosome mystery hook and display two daughter cells with a question: “How can both cells receive the same genetic information?” Students complete a quick think-pair-share, then recall the role of the nucleus, chromosomes and DNA from previous lessons.

2. 5–15 min · Explicit teaching. Use the mitosis teaching sequence to introduce the purpose of mitosis and the four required stages. Teacher models the visual clues: chromosomes condense in prophase, line up at the equator in metaphase, separate to opposite poles in anaphase, and form two nuclei in telophase. Clarify that cytokinesis is the division of the cytoplasm after nuclear division.

3. 15–25 min · Guided image analysis. Display labelled and unlabelled diagrams through the guided image analysis slides. Students annotate the diagrams on the mitosis stage analysis worksheet, identifying chromosome position, spindle activity and nuclear membrane changes. Pause after each image for whole-class checking and correct misconceptions, particularly confusing prophase with metaphase.

4. 25–40 min · Collaborative sequencing task. In groups of four or five, students use the image set on the mitosis stage analysis worksheet to sequence stages and complete a comparison table. Each student takes a role: reader, sequence checker, evidence finder or reporter. Groups must justify each stage using the sentence frame, “This is ___ because the chromosomes are ___.”

5. 40–51 min · Independent explanation. Students complete the short-answer section of the mitosis stage analysis worksheet independently. They explain how replicated chromosomes are separated and why the resulting daughter cells are genetically identical. Teacher conferences with students who need support and checks that students use the terms chromosome, spindle, nucleus and identical accurately.

6. 51–57 min · Feedback and application. Return to the application and discussion slides and present a partially completed sequence and a cell-repair scenario, such as replacement of damaged skin cells. Students identify the missing stage and explain how mitosis supports growth or repair. Invite two groups to share evidence-based responses.

7. 57–60 min · Exit check. Display the final prompt on the plenary and exit prompt: “Explain in two sentences how mitosis produces two genetically identical daughter cells.” Students submit their response before leaving.

Resources

• the complete mitosis teaching deck
• the mitosis stage analysis worksheet
• Projector or interactive display
• Whiteboard and markers
• Student pens, highlighters and coloured pencils
• Enlarged mitosis diagrams or microscope images
• Timer
• Exit-response collection tray or digital submission tool

Assessment

• During retrieval and guided analysis, question students about the function of chromosomes, the nucleus and spindle fibres; use responses to identify misconceptions.
• Check group sequences and require students to justify decisions using chromosome behaviour rather than relying only on memorised stage names.
• Use the independent worksheet and exit response to assess whether students can identify stages and explain genetic similarity. Look for accurate sequencing, correct terminology and the link between chromosome separation and identical daughter cells.

Differentiation

• Provide a word bank, colour-coded stage cues and sentence starters on the mitosis stage analysis worksheet for students requiring support, including EAL/D learners.
• Pair students strategically and allow students to explain their sequence orally before writing the formal response.
• Use enlarged, high-contrast diagrams and read instructions aloud for students with visual, literacy or processing needs; provide additional time where required.
• Extend confident students by asking them to explain what could happen if spindle fibres failed to separate chromosomes correctly, linking the response to consequences for daughter cells.