1. Respiratory system Lesson 4 Gaseous exchange

2. LO – Level 4 –To state where oxygen gets into the blood and how it is transported around the body. Level 6 – To explain how oxygen gets into the blood. Level 7 – To explain how the lungs are adapted to their job.

3. Keywords Alveoli Diffusion Gaseous exchange Capillaries Red blood cells Ciliated cells Cilia

4. The alveoli

5. Gas exchange

6. The alveoli are adapted to make gas exchange in lungs happen easily and efficiently.

7. Features of the alveoli that allow gas exchange They have moist, thin walls (just one cell thick) They give the lungs a really big surface area They have a lot of tiny blood vessels called capillaries.

10. How is the respiratory system adapted for its function? StructureAdaptation - enables it to do its job properly! Lungs contain thousands of alveoli Gives lungs a large surface area for absorbing oxygen and excreting carbon dioxide Alveoli walls are only one cell thick and are surrounded by many capillaries Allows substances to diffuse easily into and out of the blood Goblet cells secrete mucusTraps dust, dirt and germs Cilia on ciliated epithelial cells waft! Tiny hairs that sweep mucus out of the lungs

11. The passage of air through the body: The lungs are positioned inside the ………….. …………….. The ………… form a cage protecting them. The ………..lung has ………… lobes and is bigger than the ………… lung which only has ………... The action of breathing means that the lungs are constantly moving in and out. In order to prevent friction, the lungs are surrounded by the ………………. ………………… This is a complete lining which is smooth and has a moist, slimy mucus. two three right left chest cavity pleural membrane ribcage