Today you learned how your unsung epithelial tissue creates the inner and outer boundaries that keep you alive.

今天你们学到了无名的上皮组织是如何创造内部和外部边界，让你们活着的。

I mean, currently the outer boundary of human life is somewhere around 110 and 115.

我的意思是，目前人类生命的外边界大约在 110 和 115 之间。

Humans have launched several unmanned ambassadors  to the outer boundary of our solar system.

人类已经向我们太阳系的外边界发射了几艘无人驾驶大使。

In the last 50 years, we have explored and studied the outer boundary of our solar system, breaking through the heliosphere into interstellar space.

在过去的 50 年里，我们探索和研究了太阳系的外边界，突破了日球层进入星际空间。

Since Project Daedalus, several revolutionary spacecraft have made the perilous journey to the outer boundary of our solar system, but the first was actually unplanned.

自代达罗斯计划以来，几艘革命性的航天器已经进行了前往我们太阳系外边界的危险旅程，但第一个实际上是计划外的。

And just like that chaotic cafeteria packed with middle-schoolers -- we'd be hopeless messes without our hierarchy of organization, our inner and outer boundaries, and the ability of our systems to communicate with each other.

就像那个挤满了中学生的混乱的自助餐厅，如果没有组织层级，我们的内外界限，以及我们的系统相互沟通的能力，我们会变成一团糟。