So, these are all involved with our ability to maintain homeostasis by exchanging materials with the external environment.

这个过程关乎人体维持内稳态的能力,内稳态通过与外环境进行物质交换来实现

耶鲁公开课 - 生物医学工程探索课程节选

The respiratory system, for example, the renal system, the digestive system, these are examples - three examples of organ systems that contact the external environment.

例如,呼吸系统,泌尿系统,消化系统,这些系统,这三个系统,与外环境相联系

耶鲁公开课 - 生物医学工程探索课程节选

We've talked about the interesting way in which the digestive system contacts the external environment.

我们会讲到,消化系统与外环境之间十分有趣的联系

耶鲁公开课 - 生物医学工程探索课程节选

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