Answer to Question 1
Gas exchange may be impaired if the alveolar septa are thickened and scarred. It also may be impaired if pulmonary blood flow to a portion of the lung is obstructed or by blockage of pulmonary capillaries by fat emboli or foreign material. Also, if the pulmonary alveoli become filled with fluid or inflammatory exudates, inspired air cannot enter the diseased alveoli, and pulmonary gas exchange is impeded.
Answer to Question 2
More technically difficult to perform; may lead to spontaneous abortion and limb deformities
Visualization of heat exchange in an ectotherm and an endotherm.
Columbian Exchange
A hearing-impaired patient using an interpreter.
A model for RecA-mediated strand exchange
The RecA strand exchange reaction as shown from single-molecule studies
Countercurrent Exchange