各段肾小管对 Na+的重吸收率, 最大的是
A. 近端小管
B. 远曲小管
C. 髓襻
D. 集合管
尿液中的K+主要来源于
A. 原始尿液中的K+
B. 远曲小管和集合管上皮细胞分泌的
C. 近曲小管上皮细胞分泌的
D. 髓襻上皮细胞分泌的
_____, also called the Chinese New Year, is China's most important festival that falls on the first day of the first lunar month each year. Family members gather just as westerners do on Christmas.
A.The Spring Festival
B.The Mid-Autumn Festival
2.The major custom of the Qingming Festival is _______.
A.Burning firecrackers
B.tomb sweeping