Question

Draw on a single set of axes the oxygen binding curves (i.e. YO2 vs. pO2) for a Hemoglobin with typical oxygen affinity and for bar-headed goose Hemoglobin. Include a detailed legend that provides enough information .

Answer 1

Answer:

High altitude environments pose a number of unique physiological challenges to animal life. In addition to the characteristically cold temperatures, high altitude environments also have lower partial pressures of oxygen (relative to low altitude environments at similar latitudes). Since there is less oxygen in each breath, there is an accompanying reduction in the O₂ saturation of arterial blood.

In order to compensate, physiological adjustments are required to ensure an adequate supply of O₂ to the cells of aerobically metabolizing tissues. Although the genetic basis of low oxygen (hypoxia) tolerance has yet to be fully elucidated in any species, evidence from a number of animals suggests that modifications of hemoglobin function often plays a key role in adaptation to high-altitude hypoxia.

Baor-heavded goose Domestie bird 3 to 60 30 20 T 10 20 30 40 50 60 80 poy

One strategy for adapting hypoxic conditions is through altered O₂ affinity of hemoglobin. In several high-altitude species, various hemoglobin mutations result in increased O₂ affinity by stabilization of the oxy hemoglobin form. Animals faced with hypoxic conditions may display adaptations in their hemoglobin.

For example, the oxygen-binding curves of the bar-headed goose are significantly left-shifted in comparison to the domestic duck (and most other birds).