蛋白质同定于细胞膜上的方式可能反映它们在细胞中的功能。第一种是蛋白质仅固定于膜表面;第二种则是部分插入膜内,部分伸出膜外;第三种是跨膜两端的蛋白质。外 The way proteins bind to the plasma membrane may reflect their function in the cell. The first is that the protein is immobilized only on the surface of the membrane; the second is partially inserted into the membrane and partly out of the membrane; and the third is the protein across the membrane. outer