Gas exchange and the transport of oxygen in living organisms：練習問題

Which of the following describes the correct pathway of air through the human gas exchange system during inhalation?

The Bohr effect describes how the presence of carbon dioxide affects the transport of oxygen. How does a high partial pressure of \(CO_{2}\) in respiring tissues affect the oxygen-haemoglobin dissociation curve?

A small mammal has a higher surface area to volume ratio than a larger mammal. Which of the following correctly relates this ratio to the mammal's metabolic rate and the oxygen-binding properties of its haemoglobin?

In humans, the mechanism of breathing out (expiration) during quiet breathing is primarily a passive process. Which of the following changes leads to this process?

Which statement best explains how the structure of the alveolar epithelium is adapted to facilitate a rapid rate of gas exchange?

State two structural features of the alveolar epithelium that adapt it for efficient gas exchange in the human lung.

Contrast the mechanisms used by terrestrial insects and xerophytic plants to minimize water loss while still allowing for the exchange of gases with the atmosphere.

Explain how the accumulation of lactate in the muscle fibers of an insect during flight results in a faster rate of diffusion of oxygen through the tracheal system.

Insects have a specialized system for gas exchange that differs significantly from mammals due to their small size and exoskeleton.
a) Describe the pathway taken by oxygen from the atmosphere to the respiring tissues of an insect.
b) Explain how the tracheal system is adapted to minimize water loss while maintaining efficient gas exchange.
c) During periods of high activity, insects may produce lactate in their muscles. Explain how the accumulation of lactate in muscle cells affects the rate of gas exchange via the tracheoles.

The graph in the provided figure shows the oxygen-haemoglobin dissociation curves for two different mammals, Species A and Species B. Species A lives at sea level, while Species B lives at a high altitude where the partial pressure of oxygen (\(pO_2\)) is much lower.
a) Explain the S-shaped (sigmoidal) nature of the oxygen-haemoglobin dissociation curve.
b) Describe and explain the advantage to Species B of having a curve shifted to the left of Species A.
c) Explain the Bohr effect and its importance during periods of high metabolic activity in muscle tissues.