Explain how the body uses a negative feedback cycle to return blood glucose levels to normal after a meal.

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)

Blood glucose rises after a meal.
The pancreas senses the rise and releases insulin.
Insulin stimulates cells to take up glucose and convert it to glycogen for storage in liver and muscle.
Glucose levels fall back to the normal range, completing the negative feedback loop.

Examiner tips

Use the exact sequence: rise → pancreas → insulin → glycogen storage → return to normal.
Show cause–effect links and mention the pancreas and insulin explicitly.
Keep each point brief but complete; avoid extra detail that wastes marks.

Common mistakes

Mixing up insulin with glucagon or omitting the pancreas.
Failing to mention glycogen storage or the return to normal levels.
Writing in a narrative style instead of concise, factual statements.

Mark scheme (4 marks)

Blood glucose level rises after a meal
The pancreas detects the rise and releases insulin
Insulin causes glucose to be converted to glycogen (stored in the liver/muscles)
Blood glucose level returns to normal / optimum, reversing the original change

Key terms in this question

negative feedback cycle · blood glucose