Nature of science:
Scientists have a role in informing the public—scientific research has led to a change in public perception of smoking.
Understandings:
Oxygen dissociation curves show the affinity of hemoglobin for oxygen.
Carbon dioxide is carried in solution and bound to hemoglobin in the blood.
Carbon dioxide is transformed in red blood cells into hydrogencarbonate
ions.
The Bohr shift explains the increased release of oxygen by hemoglobin 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 hemoglobin is different from adult hemoglobin allowing the transfer of
oxygen in the placenta onto the fetal hemoglobin.
Applications and skills:
Application: Consequences of high altitude for gas exchange.
Application: pH of blood is regulated to stay within the narrow range of 7.35
to 7.45.
Application: Causes and treatments of emphysema.
Skill: Analysis of dissociation curves for hemoglobin and myoglobin.
Skill: Identification of pneumocytes, capillary endothelium cells and blood
cells in light micrographs and electron micrographs of lung tissue.