B1 EXCHANGING SUBSTANCES

  • Created by: kerrylond
  • Created on: 01-05-18 20:27

EXCHANGING SUBSTANCES

  • Gas exchange happens in the LUNGS
  • Job of lungs = transfer oxygen to blood and remove waste carbon dioxide
  • Lungs contain lots of air sacs = alveoli, where gas exchange happens
  • Alveoli = specialised to maximise the diffusion of carbon dioxide and oxygen

ADAPTIONS - ALVEOLI
-Large surface area = 75 m squared
-Moist lining for dissolving gases
-Very thin walls
-Good blood supply

  • Inside the small intestine = covered in millions of tiny projections = villi 
  • Villi = increase the surface area, so food which has been digested is absorbed more quickly into the blood. 

ADAPTATIONS - VILLI
-Single layer of surface cells
-Very good blood supply to assist quick absorption 

PLANTS - EXCHANGING SUBSTANCES

  • Carbon dioxide diffuses into air spaces within the leaf, then it diffuses into the cells --> photosynthesis happens
  • Underneath of a leaf = exchange suface, covered in tiny holes

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B1 EXCHANGING SUBSTANCES

  • Created by: kerrylond
  • Created on: 01-05-18 20:27

EXCHANGING SUBSTANCES

  • Gas exchange happens in the LUNGS
  • Job of lungs = transfer oxygen to blood and remove waste carbon dioxide
  • Lungs contain lots of air sacs = alveoli, where gas exchange happens
  • Alveoli = specialised to maximise the diffusion of carbon dioxide and oxygen

ADAPTIONS - ALVEOLI
-Large surface area = 75 m squared
-Moist lining for dissolving gases
-Very thin walls
-Good blood supply

  • Inside the small intestine = covered in millions of tiny projections = villi 
  • Villi = increase the surface area, so food which has been digested is absorbed more quickly into the blood. 

ADAPTATIONS - VILLI
-Single layer of surface cells
-Very good blood supply to assist quick absorption 

PLANTS - EXCHANGING SUBSTANCES

  • Carbon dioxide diffuses into air spaces within the leaf, then it diffuses into the cells --> photosynthesis happens
  • Underneath of a leaf = exchange suface, covered in tiny holes

Comments

No comments have yet been made