The lungs Flashcards
Structure of lungs
1) the thorax is the top part of your body
2) Its separated from the lower part of the body by the diaphragm
3) The lungs are like 2 pink sponges and are protected by the ribcage. They’re surrounded by pleural membrane.
4) The air that you breathe in goes through the trachea. This splints into 2 tubes called bronchi, one bronchus to each lung.
5) bronchi split into progressively smaller tubes - bronchioles.
6) bronchioles finally end at small bags called alveoli where gas exchange takes place
What are alveoli and the structure of them ?
1) the lungs contains millions of little air sacs = alveoli surrounded by a network of blood capillaries. This is where gas exchanged happens.
2) The blood passing next to the alveoli has just returned to the lungs from the rest of the body, so it contains lots of co2 and very little blood.
3) oxygen diffuses out of the alveolus( high conc) into the blood ( low conc ). CO2 diffuses out of the blood ( high conc) into alveolus ( low conc) to be breathed out.
4) When the blood reaches body cells oxygen is released from RBC ( high conc) and diffuses into the body cells ( low conc)
5) At the same time, co2 diffuses out of the body cells ( high conc) into blood ( low conc) . It’s then carried back to lungs.
Calculate breathing rate in breaths per min
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