1. In Mammals GAS EXCHANGE

2.  Mammals are active so they have a high oxygen demand GAS EXCHANGE IN MAMMALS

3.  Mammals are active so they have a high oxygen demand  Mammals have a complex internal lung system for gas exchange which closely connect with a closed, double transport system. GAS EXCHANGE IN MAMMALS

4.  Mammals are active so they have a high oxygen demand  Mammals have a complex internal lung system for gas exchange which closely connect with a closed, double transport system.  Air passes first through the nasal cavity which is moist and warm. GAS EXCHANGE IN MAMMALS

5.  Mammals are active so they have a high oxygen demand  Mammals have a complex internal lung system for gas exchange which closely connect with a closed, double transport system.  Air passes first through the nasal cavity which is moist and warm.  This prevents the rest of the system from becoming too dry. GAS EXCHANGE IN MAMMALS

6.  Mammals are active so they have a high oxygen demand  Mammals have a complex internal lung system for gas exchange which closely connect with a closed, double transport system.  Air passes first through the nasal cavity which is moist and warm.  This prevents the rest of the system from becoming too dry.  Any large dust particles are trapped by hairs in the nose before they can enter the trachea. GAS EXCHANGE IN MAMMALS

7.  Mammals are active so they have a high oxygen demand  Mammals have a complex internal lung system for gas exchange which closely connect with a closed, double transport system.  Air passes first through the nasal cavity which is moist and warm.  This prevents the rest of the system from becoming too dry.  Any large dust particles are trapped by hairs in the nose before they can enter the trachea.  Food or liquid is directed to the stomach and prevented from entering the lungs by a flap of tissue called the eipiglottis. GAS EXCHANGE IN MAMMALS

9.  https://www.youtube.com/watch?v=umnnA50IDIY https://www.youtube.com/watch?v=umnnA50IDIY

10.  The trachea is strengthened and supported by rings of cartilage – this is flexible to allow neck movement, but strong enough not to collapse and shut off the trachea as the neck moves. GAS EXCHANGE IN MAMMALS

11.  The trachea is strengthened and supported by rings of cartilage – this is flexible to allow neck movement, but strong enough not to collapse and shut off the trachea as the neck moves.  The trachea is covered in a film of mucus, which traps small particles. The particles are brought up from the trachea to the nasal cavity by the beating cilia. The mucus and other waste products are swallowed or ejected. GAS EXCHANGE IN MAMMALS

12.  The trachea is strengthened and supported by rings of cartilage – this is flexible to allow neck movement, but strong enough not to collapse and shut off the trachea as the neck moves.  The trachea divides into two bronchi, one to each lung. The bronchi divide into bronchioles (which don’t have cartilage bands), these divide further ending in minute sacs called alveoli. GAS EXCHANGE IN MAMMALS

13. BRONCHI

14.  https://www.youtube.com/watch?v=Aw9OJLTlClQ https://www.youtube.com/watch?v=Aw9OJLTlClQ

15.  Alveoli provide a very large, moist surface for gas exchange – this is where oxygen diffuses into the blood capillaries and into red blood cells. GAS EXCHANGE IN MAMMALS

16. ALVEOLI

17.  The oxygen is picked up by haemoglobin for transport to the body cells – and carbon dioxide diffuses out of the cells into the blood plasma for transport to the alveoli. GAS EXCHANGE IN MAMMALS

18.  https://www.youtube.com/watch?v=Cy1lfZAIojs https://www.youtube.com/watch?v=Cy1lfZAIojs  https://www.youtube.com/watch?v=KqZc1JqArco https://www.youtube.com/watch?v=KqZc1JqArco  WARNING – NOT FOR SQUEAMISH GAS EXCHANGE IN MAMMALS