Those red blood cells get engulfed by the liver, who helps just try to clean up any messy red blood cells in the system.

这些红细胞被肝脏吞噬，肝脏的作用是帮助清理系统中任常的红细胞。

The parasite that causes malaria, though, can only complete its life cycle in normal, round red blood cells.

然而，导致疟疾的寄虫只能在常的圆形红细胞中完成其命周期。

And that mutation caused a red blood cell that normally looks like this to be made like that.

这种突变导致原本常的红细胞形态变成了这样。

Carriers are less susceptible to malaria, because they make some sickled red blood cells, but they make enough normal red blood cells that they aren't negatively affected by sickle cell anemia.

携带者易感染疟疾， 因为他们会产一些镰状红细胞，但他们会产足够多的常红细胞， 因此会受到镰状细胞性贫血的负面影响。