| The structure of the Haemoglobin | - 4 polypetide chains Quaternary structure
- |
| Oxyhaemoglobin | Oxygen bound to the Haemoglobin |
| Oxygen dissociation | Oxygen detaches from the haemoglobin |
| Affinity | How strongly oxygen is attracted to the haemoglobin |
| % haemoglobin saturation for oxygen | % of haemoglobin attracts oxygen
number of oxyhb mols/ maximum number of hb molecules x 100 |
| Partial pressure of Oxygen pp0 or po2 | concentration of oxygen |
| Partial pressure of Carbon dioxide ppCO2 or pCO2 | concentration of co2 |
| THE LUNGS | high po2
therefore hb molecules have a high affinity for oxygen
therefore oxygen molecules bind to hb
hb becomes nearly 100% saturated |
| THE MUSCLES | low p02 due to respiration in cells
therefore hb molecules have a lower affinity for oxygen
therefore oxygen dissociates from hb so oxygen can diffuse into the tissue cells |
| Oxygen haemoglobin curve shape | Sigmoid - S |
| Point to remember | 1. Partial pressure
2. Affinity hb and ox
3. 02 binds or dissociates |
| The Bohr effect | -curve shifts right
- Decreases affinity so more dissociation of 02 from Hb
- The greater pCo2 the more 02 dissociation
- released so more respiration |
| The effect of temp on O2 curve | Higher temp means more respiration as it releases heat so more c02 levels so less affinity so more disassociation |
| Adaptions of the haemoglobin | -foetal hb has higher affinity than maternal, so oxygen from mum can bind to it
- high altiudes = more hb |
