Essential Idea:
Red blood cells are vital in the
transport of respiratory gases
Understandings:
- Oxygen dissociation curves show the affinity of haemoglobin for oxygen
- Carbon dioxide is carried in solution and bound to haemoglobin in the blood
- Carbon dioxide is transformed in red blood cells into hydrogen carbonate ions
- The Bohr shift explains the increased release of oxygen by haemoglobin in respiring tissues
- Chemoreceptors are sensitive to changes in blood pH
- The rate of ventilation is controlled by the respiratory control centre in the medulla oblongata
- During exercise the rate of ventilation changes in response to the amount of CO2 in the blood
- Fetal haemoglobin is different from adult haemoglobin allowing the transfer of oxygen in the placenta onto the fatal haemoglobin
Applications:
- Consequences of high altitude for gas exchange
- pH of blood is regulated to stay within the narrow range of 7.35 to 7.45
- Causes and treatments of emphysema
Skills:
- Analysis of oxygen dissociation curves for haemoglobin and myoglobin
- Identification of pneumocytes, capillary endothelium cells and blood cells in light micrographs and electron micrographs of lung tissue