Others have only one flagellum. The flagella rotate, pushing the bacteria through the water.

而有的细菌只有根毛。毛的旋转可以推动细菌在水中行进。

Well, choanoflagellates have little flagella that whip back and forth to move them from place to place.

领虫有很小的毛，毛来回摆动，让它们从方移动到另方。

As in modern specimens, the fossil sperm lacked a flagellum, or tail.

与现代标本样，化石精子没有毛或尾巴。

The process by which a spermatid elongates, grows a tail, or flagellum, and officially becomes a mobile sperm is called spermiogenesis.

精子细胞伸长、长出尾巴或毛并为移动精子的过程称为精子形。

And they wanted to focus on the flagellum because it's that whiplike tail that propels a sperm forward.

霍普金：他们想把重点放在毛上，因为状的尾巴推动精子前进。

The cells use rotating flagella to propel towards the surface of the rock, which they attach to with the help of sticky appendages.

细胞利用旋转的毛游向石头的表面，然后利用富有粘性的附属物附着于石头上。

It has pili and a single polar flagellum, kind of like a tail, at one end which it uses for movement through the gastrointestinal tract.

它含有菌毛和条像尾巴的毛；毛可以移动，使其能在胃肠道中移动。

Now, how that flagellum beating and how the movement of that structure changes in response to changing flow conditions was completely ignored.

Nosrati：现在，毛的跳动以及该结构的运动如何随着流动条件的变化而变化被完全忽略了。

Over billions of years of evolution, nature has come up with lots of molecular machines, from whip-like flagella that help cells move, to enzymes that catalyze chemical reactions.

在几十亿年的进化过程中，大自然产生了许多分子机器，从帮助细胞运动的状毛体到催生化学反应的酶。