A person with Type 1 diabetes does not produce sufficient insulin. Explain how this affects blood glucose levels and why this is dangerous to the person.

AQA GCSE Biology (8461) — 4.5.1 Homeostasis · Explain · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

1. Blood glucose levels rise after a meal because insulin is not produced.
2. Without insulin, cells cannot take up glucose from the blood.
3. Cells cannot respire properly, so they cannot release energy efficiently.
4. The high blood glucose draws water out of cells by osmosis, damaging tissues such as kidneys, eyes and nerves.

Examiner tips

  • Use the exact terms 'insulin', 'glucose', 'cells cannot take up', 'respire', 'osmosis', 'tissues', 'kidneys, eyes, nerves'. Show the causal chain: no insulin → high glucose → impaired uptake → energy loss → osmotic damage. Keep each point concise and directly linked to the mark scheme.
  • common_mistakes
  • :
  • Using vague phrases like 'the body is affected' instead of specific mechanisms. Forgetting to mention the osmotic effect or the specific organs damaged.

Mark scheme (4 marks)

  1. Blood glucose levels rise / remain high (after eating) because insulin is not produced / not sufficient
  2. Cells cannot absorb / take up glucose from the blood (because insulin is absent / insufficient)
  3. Cells cannot respire / release energy effectively / properly
  4. High blood glucose causes water to move out of cells by osmosis, damaging tissues / organs (e.g. kidneys, eyes, nerves)

Key terms in this question

Type 1 diabetes · insulin · blood glucose

Related

More Homeostasis questions

▶ Try answering this question with AI marking (free) →