The bicarbonate buffer system is an effective physiological buffer near pH 7.4, because the H2CO3 of blood plasma is in equilibrium with a large reserve capacity of CO2 in the air space of the _______.
【单选题】?Read the article below about product life cycles and the questions on tile opposite page. ?For each question (13-18), mark one letter (A, B, C or D) on your Answer Sheet for the answer you choose. Sa...