Blood Sugar Control
Insulin lowers blood glucose; glucagon raises it.
About this topic
The pancreas monitors blood glucose. When it rises after a meal, beta cells release insulin, which causes liver and muscle cells to take up glucose and store it as glycogen, lowering blood sugar. When it falls, alpha cells release glucagon, which makes the liver convert glycogen back to glucose.
In type 1 diabetes the pancreas makes no insulin, so patients inject it; in type 2, cells become resistant, linked to diet and obesity. This is a classic negative feedback system.
After a sugary snack, blood glucose rises, insulin is released and cells absorb the glucose; between meals glucagon prompts the liver to break glycogen into glucose. In type 1 diabetes the immune system destroys beta cells, so patients must inject insulin; in type 2, cells respond poorly to insulin, linked to obesity and managed by diet, exercise and medication.
Symptoms of diabetes include thirst, frequent urination and tiredness, and glucose can be found in the urine. Untreated, it can damage eyes, kidneys and nerves. Healthy blood glucose is about 4 to 8 millimoles per litre. Students often think insulin and glucagon are the same; they have opposite effects, and are an example of two hormones working antagonistically to keep glucose stable.
Key ideas
- Pancreas senses glucose
- Diabetes disrupts control
- Diet and exercise help
Quick check
Use cases: where Blood Sugar Control helps
- Homework: review the key idea behind Blood Sugar Control before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Blood Sugar Control without notes.
- Visual learning: play with the interactive lab to see how Blood Sugar Control changes when you adjust its inputs.
- Teaching a friend: explain Blood Sugar Control in your own words, then compare your version with the key ideas.
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Frequently asked questions
What is Blood Sugar Control?
Insulin lowers blood glucose; glucagon raises it.
What will I learn in Blood Sugar Control?
Pancreas senses glucose. Diabetes disrupts control. Diet and exercise help.
Is Blood Sugar Control part of Biology?
Yes. It is one of 150 Biology topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Blood Sugar Control lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Blood Sugar Control?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.