14.4.2: Blood Glucose Control
The Homeostatic Balance
SYLLABUS FOCUS: Understanding how Insulin and Glucagon maintain blood glucose homeostasis, the role of the Liver in glucose ↔ glycogen conversion, and Type 1 Diabetes.
The Balance: Blood Glucose Homeostasis
Why Does Glucose Matter?
- Energy Source: Glucose is used in Respiration to release ATP (cellular energy).
- Homeostasis: Blood glucose must stay within a narrow range (~90 mg/dL).
- Danger Zone: Too high → Diabetes damage. Too low → Brain shutdown.
After Eating (High Glucose)
The Problem:
Blood glucose rises above normal range.
The Solution:
- Pancreas detects high glucose
- Pancreas secretes INSULIN
- Liver converts soluble Glucose → insoluble GLYCOGEN
- Blood glucose decreases
During Fasting (Low Glucose)
The Problem:
Blood glucose falls below normal range.
The Solution:
- Pancreas detects low glucose
- Pancreas secretes GLUCAGON
- Liver converts insoluble Glycogen → soluble GLUCOSE
- Blood glucose increases
🎯 KEY CONCEPT: Negative Feedback
This is a negative feedback loop. When glucose rises, the response (insulin) brings it back down. When it falls, the response (glucagon) brings it back up. This maintains homeostasis(stable internal environment).
LIMITLESS IGCSE Biology | Syllabus 0610 (2026-2028) | 14.4.2: Blood Glucose Control
Sign In to Keep Going
You've reached the end of the free preview. Sign in — and upgrade to Plus or Pro — to keep going with Biology.
Full Access
Unlock all 194 lessons