Organisms: Absorption and Transport – Year 9
How Do Nutrients Enter and Travel Around the Body? (PPT + Worksheet)

This lesson explores how the small intestine is specially adapted to absorb nutrients efficiently and how these nutrients are transported around the body. Pupils describe the structure of the small intestine and its lining, explain how villi and microvilli maximise surface area for absorption, identify how glucose and amino acids enter the bloodstream, and use a diffusion model to demonstrate how nutrients move into cells. The lesson concludes by linking the digestive system to the circulatory system to show how absorbed nutrients reach every part of the body.

• Describe the structure of the small intestine and its lining — long, folded tube with a highly specialised inner surface.
• Explain how villi and microvilli maximise surface area for absorption — increasing efficiency of nutrient uptake.
• Identify how glucose and amino acids enter the bloodstream — diffusion and active transport into capillaries.
• Demonstrate how nutrients move into cells using a diffusion model — understanding concentration gradients in living systems.
• Link the digestive system to the circulatory system for nutrient delivery — how absorbed molecules are transported to tissues.

• KS3 Biology: Digestion, absorption and transport
• Working Scientifically: Modelling, explanation and application of biological processes

Some visuals in this resource were made with AI to help bring ideas to life and support student understanding.