":"/gcse/biology/edexcel/questions","basePath":"/gcse/biology/edexcel/mitosis-growth-and-stem-cells/questions","formulaUrl":null,"initialIndex":56,"initialQuestionWindow":[{"id":"a6826d86-919c-43ce-baa7-a2dec8ded9d7","revisionId":"c63dd5e8-06b7-4e5d-8d66-afcccb967ef0","questionNumber":null,"questionType":"LA","specification":"The diagram below shows a cell during a particular stage of mitosis.\n\n![Cell Division Stage](https://assets.mathsgenie.co.uk/aqa-qb/b1ae0f0c-dd56-443e-bf26-f233c5476a41.png)","difficulty":6,"difficultyBand":"easy","totalMarks":2,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"c0341fb8-17e3-49ba-b38f-0a46263c5bb5","label":null,"content":"Describe two processes that occur in the cell during this stage.","markscheme":"- Centromeres split / divide (allowing sister chromatids to separate) M1\n- Chromatids (or chromosomes) are pulled / move to opposite poles of the cell by the contracting / shortening spindle fibres A1","marks":2,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"identify_anaphase_processes","label":"Identify the mitosis processes","steps":[{"type":"text","order":0,"title":"Read the diagram","content":"The chromosomes are no longer lined up across the middle of the cell. Instead, two groups are moving apart towards the opposite ends, or **poles**, of the cell. This identifies the stage shown as anaphase.\n\nUse the diagram already provided: each V-shaped structure is a chromatid moving towards one pole.","highlights":[{"text":"Describe two processes that occur in the cell during this stage.","location":"specification"}]},{"type":"text","order":1,"title":"State the separation","content":"First, state what makes the two halves of each chromosome separate:\n\n$$\\text{The centromeres divide, allowing sister chromatids to separate.}$$\n\nA **centromere** is the region joining two sister chromatids. This precise process earns **M1**.","highlights":[{"text":"Describe two processes that occur in the cell during this stage.","location":"specification"}]},{"type":"text","order":2,"title":"Explain the movement","content":"Then describe both the movement and its cause:\n\n$$\\text{Spindle fibres shorten, pulling the chromatids to opposite poles of the cell.}$$\n\nThis earns **A1** because it says that chromatids move to opposite poles **and** that contracting (shortening) spindle fibres pull them.","highlights":[{"text":"Describe two processes that occur in the cell during this stage.","location":"specification"}]}]}],"generatedAt":"2026-07-22T08:26:03.220Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"a6d335d8-6906-447f-840d-c7b04fe5140c","revisionId":"dec5fd5a-b0b4-461c-81f6-1871c69a8cd3","questionNumber":null,"questionType":"LA","specification":"During the preparation of garlic root tip squash slides to observe stages of mitosis, root tips are heated in a vial of dilute hydrochloric acid.","difficulty":3,"difficultyBand":"easy","totalMarks":2,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"0a031b6b-f62c-4e3f-b464-902b55807d8b","label":null,"content":"State **two** safety precautions that should be taken specifically when heating the hydrochloric acid.","markscheme":"- Wear safety goggles / eye protection to protect eyes from splashes of hot, corrosive acid B1\n- Use a water bath to heat the acid to provide controlled heating and prevent spitting B1\n- Use tongs or a test-tube holder to handle the hot vial to prevent burns to the skin B1\n- Place in a fume cupboard or well-ventilated area to avoid inhaling toxic or irritating acid vapours B1","marks":2,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"heating_acid_safely","label":"Match hazards to precautions","steps":[{"type":"text","order":0,"title":"Protect your eyes","content":"Wear safety goggles to protect your eyes from splashes of hot, corrosive acid.\n\nThis is one valid, heating-specific precaution,

Mitosis, growth and stem cells

Question 39

Mitosis, growth and stem cells Questions

Mitosis, growth and stem cells

Question 39

Mitosis, growth and stem cells Questions