Glucose Control | GCSE Biology

Homeostasis and response

Lesson overview

This lesson introduces the core biology idea, the useful equipment and the calculation or data skills used on this page.

Focusblood glucose control and diabetes

Time45-60 minutes

EquipmentNotebook, calculator and a pen for labelled diagrams.

Practical linkblood-glucose data and treatment evidence

Maths tagsconcentration, graph trends and feedback control

What you will learn

Describe the key biology ideas behind blood glucose control and diabetes.
Use precise GCSE command-word language in explanations.
Apply the idea to unfamiliar cells, organisms, data or practical contexts.
Check answers using units, labelled diagrams, observations, calculations or biological evidence where relevant.

Core knowledge

Big idea: Blood glucose control depends on insulin and glucagon acting in opposite directions through negative feedback.
This lesson focuses on blood glucose control and diabetes. A strong answer explains the biology and points to evidence such as feedback graphs, receptor-effector pathways, hormone levels and response data.
Insulin: a hormone that lowers blood glucose concentration.
Glucagon: a hormone that raises blood glucose concentration.
Pancreas: an organ that secretes insulin and glucagon to help control blood glucose.
Use the model as a thinking route: Blood glucose rises after eating -> Insulin lowers glucose by moving it into cells -> Negative feedback returns levels towards normal.
Likely question evidence: blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams. Use it to justify the explanation, not as decoration.
When numbers or graphs appear, show working with concentration, graph trends and feedback control and finish by saying what the result means biologically.

Blood glucose control and diabetes infographic

Infographic explaining GCSE Biology blood glucose control, including insulin, glucagon, the pancreas, negative feedback, glycogen storage and diabetes treatment checks. — Use this visual to follow how insulin and glucagon return blood glucose concentration towards the normal range.Download visual

Glucose Control practice set

Use the worked examples and practice questions on this page as a complete study task: learn the definitions of insulin and glucagon, summarise the infographic in your own words, then answer the questions using the data, equations and observations given here. Check every answer for concentration, graph trends and feedback control.

Clear explanation

First secure the anchor idea: blood glucose control and diabetes. In ordinary language, this means using insulin, glucagon and pancreas to explain what is happening, not just spotting those words in the question.

Next look for the evidence. In this lesson it is likely to come from blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams.

Then build the answer in order: Blood glucose rises after eating then insulin lowers glucose by moving it into cells then negative feedback returns levels towards normal. This stops the answer becoming a list of disconnected facts.

If the question includes data, use concentration, graph trends and feedback control. Keep the unit or comparison visible, then link the result back to insulin or glucagon.

Exam-ready model sentence: Insulin lowers blood glucose after it rises, while glucagon raises it when it falls too low.

Worked examples

Glucose Control: from idea to explanation

Question: Explain blood glucose control and diabetes using the model.

Start with the idea: Blood glucose rises after eating.

Add the mechanism: insulin lowers glucose by moving it into cells.

Finish with the consequence: negative feedback returns levels towards normal.

Reveal worked answer

Answer: A good answer uses insulin (a hormone that lowers blood glucose concentration), glucagon (a hormone that raises blood glucose concentration) and pancreas (an organ that secretes insulin and glucagon to help control blood glucose) in one connected explanation. For example: Insulin lowers blood glucose after it rises, while glucagon raises it when it falls too low.

Glucose Control: from evidence to marks

Question: A student has evidence from blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams. What should their answer include?

Step 1: name the useful evidence rather than writing a general fact about the topic.

Step 2: process any data with concentration, graph trends and feedback control.

Step 3: explain what the evidence shows about insulin and glucagon.

Reveal worked answer

Answer: The answer earns marks by joining evidence, method or data to a biological reason. Avoid describing a change without showing how feedback or a response returns conditions towards normal.

Quick checks

Choose an answer, then check your thinking.

1. Which answer would make glucose control clearer?

Blood glucose rises after eating and explain it using insulin Repeat the topic title without explaining it Ignore the evidence and write a memorised paragraph

2. What should you check before finishing an answer on this lesson?

Whether the answer sounds long enough Whether concentration, graph trends and feedback control and evidence such as blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams have been used where needed Whether every keyword from the page has been copied

Practice questions

Question 1

Define insulin and use it in a complete sentence about blood glucose control and diabetes.

Reveal answer and marking guidance

Answer: Insulin means a hormone that lowers blood glucose concentration. In blood glucose control and diabetes, it helps explain blood glucose rises after eating.

Marking: Credit the definition and a sentence that uses the term in the lesson context.

Question 2

Explain the main sequence in Glucose Control using the infographic.

Reveal answer and marking guidance

Answer: Blood glucose rises after eating -> Insulin lowers glucose by moving it into cells -> Negative feedback returns levels towards normal. A strong answer says why the final step follows from the first two steps.

Marking: Credit the correct order plus a biological link between the steps.

Question 3

A question gives evidence such as blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams. What should you do with that evidence?

Reveal answer and marking guidance

Answer: Identify the useful observation, method detail or data first. Then use concentration, graph trends and feedback control where relevant and explain what it shows about insulin, glucagon or pancreas.

Marking: Credit evidence use, relevant data handling and a clear biology explanation.

Question 4

A student writes: 'insulin is involved, so the answer is correct.' What detail is missing?

Reveal answer and marking guidance

Answer: Insulin means a hormone that lowers blood glucose concentration. A better answer also uses glucagon (a hormone that raises blood glucose concentration) and explains the evidence route: Blood glucose rises after eating then insulin lowers glucose by moving it into cells. An exam-ready version could be: Insulin lowers blood glucose after it rises, while glucagon raises it when it falls too low.

Marking: Credit a precise definition, a second linked term and use of evidence or model steps.

Practice ladder

FluencyRecall the key definition, symbol, structure, equation or observation.

ApplicationApply blood glucose control and diabetes to unfamiliar organisms, cells, systems, practicals or data.

Practical interpretationUse evidence, method quality, uncertainty or conclusion wording where asked to evaluate.

Maths skillUse units, ratios, graphs and significant figures accurately.

Answers and marking guidance

The exact practice answers are hidden under each question so you can try first. Marks come from using the correct biology model, choosing the right calculation where needed, keeping units with values, labelling diagrams clearly, and explaining changes with precise words such as cells, enzymes, hormones, genes, adaptation, rate, evidence and uncertainty.

Common mistakes

Using insulin, glucagon or pancreas as labels without explaining what they mean.
Forgetting to connect the answer to likely evidence, such as blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams.
Missing the maths or data habit: concentration, graph trends and feedback control.
Falling into the common trap of describing a change without showing how feedback or a response returns conditions towards normal.

Extension challenge

Create a focused revision card for blood glucose control and diabetes: three exact definitions, one model sequence, one evidence detail such as blood-glucose graphs, meal contexts, diabetes treatment data, pancreas labels and feedback diagrams, one data check using concentration, graph trends and feedback control, one common misconception, and one exam-ready explanation sentence: Insulin lowers blood glucose after it rises, while glucagon raises it when it falls too low.

Reveal answer

Example answer: A complete response names the biology model, uses accurate units or observations, and explains why the evidence supports the conclusion.