Depending on what you call external and internal environment, this path that I'm tracing here, deep within your digestive system, is really directly connected to the outside world through both ends.

基于你们所谓的外环境和内环境,我在这里我所指的消化系统内部通路,它的两端确实与外界环境直接相通

耶鲁公开课 - 生物医学工程探索课程节选

If your roommate comes in and starts trying to tell you facts about the human digestive system, " you say, "Not now."

如果你的室友跑过来开始试图,告诉你有关人类消化系统的事实，你说“现在别说“

耶鲁公开课 - 死亡课程节选