蛋白质可通过何种方式通过生物膜（）
A.溶解扩散
B.限制扩散（微孔途径）
C.主动转运
D.易化扩散
E.胞饮作用
参考答案：E
解析：促进扩散又称易化扩散，需要载体帮助由高浓度一侧向低浓度一侧扩散或转运的过程。细胞膜上有许多孔径0.4～1nm的微孔，水溶性的小分子物质和水可由此扩散通过即限制扩散。易化扩散有饱和现象，可被结构类似的物质竞争抑制，它不需要消耗能量，顺浓度梯度转运，转运速率大大超过被动转运。被动扩散过程不需要载体，也不需要能量，有溶解扩散和限制扩散（微孔途径）两种途径。脂溶性药物可通过溶解扩散通过生物膜，因为脂溶性药物可溶于液态脂质膜中，易于通过生物膜。生物膜具有流动性可以主动变形而将某些物质摄入细胞，称为胞饮，某些高分子物质，如蛋白质、多肽类、脂溶性维生素和重金属等，可按胞饮方式吸收。
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| When I was three years old just before my sister was born, my mom asked me what we should name the new baby. I said, "Let's call 1 Gravy (肉汁)!" You know, we pour gravy over meat and it tastes good! My parents found my 2 interesting, but named the new baby Caroline, instead. Having a sister 3 my life. When my sister and I played together, we 4 got into fights and got angry with each other if we did 5 wrong. It sometimes drove our parents crazy. 6 at the same time, we learned to share our things and to forgive (原谅) each other when we got 7 . In North America, there are many kinds of families, but 8 families have a boy and a girl. Of course, some have three or more. In China, most children 9 have brothers or sisters, and they have to learn those things in other ways, which is more 10 . When I 11 away to university, my sister 12 me she wished I still lived at 13 . She wasn't used to getting all the attention from my parents. But Chinese children get all the attention for all their life! Some middle school 14 in China wish they had a brother or sister. If you are one of them, I 15 a good idea for you. Treat your friends and classmates as your brothers and sisters! | ||||
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