Learning objective
Explain human body, reproduce the worked example and justify a decision in the case study.
Before you begin
Cells
Understand
Body systems cooperate. The digestive system processes food and absorbs nutrients; lungs exchange gases; blood carries oxygen and nutrients to cells.
Worked example
After a meal, nutrients cross the intestinal wall and circulation distributes them. During activity, muscles need more energy, and breathing and heart rate adjust.
Analysis and common mistakes
The heart does not manufacture oxygen: it pumps the blood that transports it.
Case study — reasoning
Explain why a problem in one system can affect others: inadequate blood flow reduces oxygen delivery even when the lungs function.
Knowledge check
Summary
Body systems cooperate. The digestive system processes food and absorbs nutrients; lungs exchange gases; blood carries oxygen and nutrients to cells.
Sources for further study and verification
AI-assisted draft · Educator review not completed · Unofficial supplementary resource