It's a facultative anaerobe so that means it can undergo respiratory and fermentative metabolism.

它是兼性厌氧菌，这意味着它可以经历呼吸和发酵代谢。

At some point, the obligate quadrupeds like the sauropods would have had facultative bipedal ancestors.

在某个时候，像蜥脚类动物这样的专性四足动物会有兼性双足动物的祖先。

That makes the environment on the enamel surface favorable for facultative anaerobic bacteria, which can metabolize sugars with and without oxygen present.

这使牙釉质表面的环境有利于兼性厌氧菌生存；兼性厌氧菌即使在缺氧的情况下也可以代谢糖类。

Let's think of some of the advantages of being a biped or facultative quadruped.

让我们想想作为双足动物或兼性四足动物的一些优势。

It's non-motile and doesn't form spores, and also, it's a facultative anaerobe, meaning that it can live with or without oxygen.

它没有运动能力，也不会形成孢子，同时，它也是兼性厌氧细菌，意味着它可以在有氧或无氧的条件下生存。

Facultative roughly means optional, so a bear can optionally walk on two legs.

兼性大致意思是可选的，所以熊可以选择用两条腿走路。

Select the advantages that a biped or facultative quadruped could gave.

选择双足动物或兼性四足动物可以提供的优势。

Bears and all animals that can, but usually don't walk on two legs can be called facultative bipeds.

熊和所有可以但通常不会用两条腿走路的动物都可以称为兼性两足动物。

Remember a facultative quadruped is a biped that has the option to move on four limbs, just not all the time.

请记住，兼性四足动物是一种可以用四肢移动的双足动物，只是不是一直都可以。

It typically bounds at high speeds on two legs, but will walk on four legs when it is moving more slowly it would be considered a facultative quadruped.

它通常用两条腿高速跳跃，但当它移动得更慢时会用四条腿行走，这将被视为兼性四足动物。