Respiration in Vertebrates

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Respiration in Vertebrates

• Surface area, perfusion , ventilation - skin,
  gills or lungs its all the same.

2
What is respiration?

• All large animals must have organs to exchange
  gases with the atmosphere. In the vertebrates
  there are three main organs.
• Skin
• Gills
• Lungs

3
What happens during respiration?

• Gases move according to the diffusion gradient.
  In the air around us or dissolved in water are
  relatively large amounts of oxygen and a small
  amount of carbon dioxide.
• Diffusion defined is movement of molecules from
  an area of high concentration to an area of low
  concentration.
• Question 1 - what is the gradient?
• Question 2 - what causes the gradient?

4
Give a helping lung - or something

• As you now know, oxygen diffuses into tissues
  because the concentration in the tissues is less.
  The problem is that large animals cannot survive
  with only simple diffusion.
• How big is too big for diffusion? It depends.

The shark is too big! It cant live without
gills!
5
How gas exchanges works

• Gills, skin and lungs have many things in common.
  They all must be moist to function, they often
  have a large thin surface area and have a special
  blood supply.
• Ask yourself why these are requirements of a
  large animals respiratory system?
• Answers

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Surface area tricks

• All gas exchangers increase their effectiveness
  by increasing their surface area. This often
  involves folds, wrinkles or sacs - anything that
  will increase area (but stay thin).

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More tricks
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Blood Flow

• Blood flow to an organ of respiration can greatly
  increase the amount of gases exchanged.
• Transporting away oxygen and bringing carbon
  dioxide to the gas exchanger.

9
Ventilation

• Moving the air or water past the respiratory
  structures greatly increases their effectiveness.

10
What is a good gas exchanger?

• Large surface area, thin epithelium.
• Blood supplied to the area (best if it is
  deoxyenated)
• Ventilate the epithelium
• Keep the epithelium moist

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Human Lungs
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Human Alveoli
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Gas Exchange
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• Why is there carbon dioxide in respirators use to
  help people recover from respiratory distress?
• Why is it important that all gas exchange
  surfaces be moist?
• Which gas causes you to increase your breathing
  rate? Why - what acid is formed?
• Why is it important for runners to have high
  levels of carbonic anhydrase in their blood?
• Why is the mammalian respiratory system superior
  to that of reptiles and amphibians?