he total cell cycle duration represented by Stage 2 and Stage 3 combined.","markscheme":"- Calculates the total number of sectors for Stage 2 and Stage 3 combined: $6 + 3 = 9$ sectors M1\n- Calculates the percentage of the total cell cycle: $\\frac{9}{40} \\times 100\\% = 22.5\\%$ A1","marks":2,"order":1,"markingRubric":null,"explanation":{"methods":[{"id":"combine_sectors","label":"Combine the sectors","steps":[{"type":"text","order":0,"title":"Add the two stages","content":"Stage 2 has $6$ sectors and Stage 3 has $3$ sectors. Add these to find the part of the cycle needed.\n\n$$6+3=9\\text{ sectors}$$\n\nThis earns M1: the two required stages have been combined.","highlights":[{"text":"Stage 2 (Mitosis) occupies $6$ sectors.","location":"specification"},{"text":"Stage 3 (Cytokinesis) occupies $3$ sectors.","location":"specification"}]},{"type":"text","order":1,"title":"Convert to a percentage","content":"There are 40 equal sectors in the whole cycle, so use the combined sectors as the fraction of the total and multiply by 100.\n\n$$\\frac{9}{40}\\times100\\%=22.5\\%$$\n\nThis earns A1 for calculating $22.5\\%$.","highlights":[{"text":"$$40$ equal sectors","location":"specification"}]}]}],"generatedAt":"2026-07-22T11:36:14.745Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"a208f5a0-fe08-4884-a175-32d6efd5dcfd","revisionId":"aee31b65-e237-4642-8a0a-82c43d683f31","questionNumber":null,"questionType":"LA","specification":"Figure 1 shows a representational pie chart about the cell cycle of a growing tissue cell.\n\n![Figure 1: Cell cycle pie chart](https://assets.mathsgenie.co.uk/aqa-qb/82613e30-6f2d-4723-8669-0fbd95790eb2.png)\n\nThe total cell cycle takes 18 hours.\nThe 'G1 & G2 phases (Cell Growth)' stage takes 620 minutes.","difficulty":6,"difficultyBand":"medium","totalMarks":4,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"58165973-e5a4-43ba-bda6-9f1c4ee7cd92","label":null,"content":"Calculate the time taken for the 'M-phase' of this cell cycle in minutes.\n\nShow your working.","markscheme":"- Converts the total cell cycle duration from hours to minutes: $18 \\times 60 = 1080$ minutes B1\n- Identifies that the 'S-phase (DNA Replication)' sector forms a right angle ($90^\\circ$) representing exactly $\\frac{1}{4}$ of the total cell cycle duration: $\\frac{90}{360} \\times 1080 = 270$ minutes M1\n- Subtracts the times of the other two stages from the total duration: $1080 - 270 - 620$ M1\n- Obtains the correct final answer of $190$ minutes A1","marks":4,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"sector_proportions","label":"Use the pie-chart sectors","steps":[{"type":"text","order":0,"title":"Use one unit","content":"The total cycle is given in hours, but the known growth stage is in minutes. Convert the whole cycle to minutes first:\n\n$$18\\times60=1080\\text{ minutes}$$\n\nThis conversion earns the **B1** mark.","highlights":[{"text":"The total cell cycle takes 18 hours.","location":"specification"},{"text":"The 'G1 & G2 phases (Cell Growth)' stage takes 620 minutes.","location":"specification"}]},{"type":"hyper_latex","block":{"nodes":[{"latex":"\\htmlData{anchor=fraction}{\\frac{90^\\circ}{360^\\circ}}=\\frac{1}{4}"},{"latex":"\\frac{1}{4}\\times 1080=270\\text{ minutes}"}]},"order":2,"title":"Find the S-phase time","description":"The right-angle sector is 90 degrees out of the full 360 degrees, so it represents one quarter of the cycle. Identifying this and calculating its time earns the M1 mark."},{"type":"hyper_latex","block":{"nodes":[{"latex":"T_{\\mathrm{M}}=1080-270-620"},{"latex":"T_{\\mathrm{M}}=190\\text{ minutes}"}]},"order":3,"title":"Find the remaining time","description":"The three sectors make up the complete cycle, so subtract the S-phase and growth times from the total. This subtraction earns the second M1 mark, and gives the final answer of 190 minutes for the A1 mark."}]}

1.2 Cell division

Question 6

1.2 Cell division Questions

1.2 Cell division

Question 6

1.2 Cell division Questions