Mass Transport (haemoglobin) Flashcards
Define mass transport
Bulk movement of liquid or gas in one direction
What determines the need for a mass tansport system and a pump?
Sa:vol
Rate of metabolism
Small sa:vol = not enough substances can be exchanged quick enough to supply volume do to long diffusion pathway
High rate of metabolism= many substances bed to be exchanged in a short amount of time= diffusion doesn’t take place quick enough
Need pump and mass transport system
Name features of mass transport system
Closed system Mechanisms to control rate of flow Mechanisms to ensure unidirectional flow Mechanisms for mass flow Suitable medium (gas or liquid)
Explain the importance of a suitable medium to a mass transport system
Must be able to Dissolve substances (e.g water)
To transport them easily
Explain the importance of having a mechanism for mass flow to a mass transport system
More rapid than diffusion
Maintain conc gradient
Explain the importance of a closed to a mass transport system
Allows all cells to be reached
Allows pressure variation for flow of substances
Explain the importance of unidirectional flow to a mass transport system
Prevent back flow
Maintain conc gradient
Explain the importance of controlling the rate of flow in a mass transport system
Adapt to the changing needs of tissues
Why are humans said to have a double circulatory system?
Blood flows in two loops to and from the heart
Pulmonary circulation (to lungs and back)
Systemic circulation (to body and back)
Two sides of the heart
Why is a double circulatory system required in humans?
Allows high pressure to be maintained
Pa reduced in lungs as goes through pulmonary capillaries
Low pa= slow flow= wouldn’t reach tissue fast enough, not returned to heart fast enough
Name arteries and veins supplying kidneys
Renal arteries/veins
How are redblood cells adapted for oxygen transport?
Biconcave disc= flexible (scrap along cappilary walls to provide short diffusion pathway) + short diffusion pathway (thin middle) + larger sa:vol
No organelles= more space for haemoglobin + flexible
Small= compressed against capillary walls (sdp)
Why is it an advantage for rbc to be flexible?
Allows them to scrap along and be compressed against capillary walls= sdp
Describe 1° structure of haemoglobin
Specific sequence of Amino acids
Polypeptide chains=
2 X alpha
2 X beta
Describe 2° structure of haemoglobin
Polypeptide chains coil into alpha helices
Describe 3° structure of haemoglobin
Polypeptide chains fold again into specific 3D shape