Essay on Biology and the Properties of Gas Exchange Surfaces

1215 Words 5 Pages
Properties of Gas exchange surfaces
Alveolus – Air sac in the lungs
• Hundreds of thousands in lungs
• Increase lungs SA

SA:V ratio = Surface area Volume

Diffusion
0.5 cm cube – 2mm cubed of non dyed agar
1cm cube – 5mm cubed of non dyed agar
2cm cube – 18mm cubed of non dyed agar

DIFFUSION IS QUICKER WITH SMALLER SA’s

Alveoli are so small.
• Diffusion is fast - blood capillary nearby
• Thin walls (alveoli and capillary) (one cell thick)
• Numerous Alveoli – Increases SA of Lungs (Each alveolus is small for quick diffusion)
• Lots of blood capillaries next to alveoli
• LUNGS = EFFICIENT GAS EXCHANGE

SA = rate of diffusion Difference in concentration gradient = Rate of diffusion Thickness of
…show more content…
Haemoglobin

Globular and Fibrous
Globular - Structure
• Compact spherical shape (polypeptide chains, highly folded)
• Soluble (hydrophilic outside)
• 3D
• Not very stable (structure easily disrupted)
Globular - Function
• Enzymes
• Antibodies
• Transport
• Pigments (haemoglobin)
• BIND TO OTHER SUBSTANCES

Fibrous – Structure
• Long Chains (straight, no fold)
• Cross linked for added strength
• Insoluble
• Very stable and strong
Fibrous – Function
• Keratin (hair, skin, collagen in the skin)
• Tendons
• Bones
• Cartilage
• Blood Vessel Walls

Cell Membrane Structure
CF IS CAUSED BY A FAULTY PROTEIN IN THE SURFACE MEMBRANES OF EPITHELIAL CELLS

Protein – (many uses) organic compounds made of Amino Acids
Epithelial Cells – Outside surface and tube lining (breathing system)

BILAYER – Double Layer (made up from phospholipid = phospholipid

Related Documents

NP-FW50 Battery for Sony Alpha A6500 A6300 A6000 A7r A7 + LCD Dual USB Charger | TV Shows | Recharge en magasin