Cambridge Book 8 Unit 2.2 Gas exchange week 2.pptx

Gas exchange

1. Gas exchange Week 2 Grade 7

2. Write these keywords into your notebooks

3. Definitions Alveoli are air sacs in the lungs, where gas exchange takes place with the blood Capillaries are the smallest type of blood vessel Gas exchange is the movement (by diffusion) of gases into and out of organisms; in the lungs, oxygen diffuses into the blood and carbon dioxide diffuses out Diffusion is the net movement of a substance from a place of higher concentration, as a result of the random movement of particles

4. Definitions Haemoglobin is a red pigment in red blood cells that combines reversibly with oxygen and transports oxygen from the lungs to all the respiring cells Analogy is the use of one structure, idea or process to explain another Limewater is a dilute solution of calcium hydroxide; it goes cloudy when mixed with carbon dioxide Expired air is the air that is breathed out Inspired air is the air that is breathed in

5. The structure of an air sac

6. What did you learn from the video? What did you learn about diffusion?

7. Learner Book P14

8. Learner Book P16

9. WB P5

10. WB P6