Final answer:
The term 'extra corporeal' refers to activities happening outside the body, such as kidney dialysis. The mucosa is the lining of body cavities exposed to the external environment.
Step-by-step explanation:
The term referring to outside the body is extra corporeal. This term is often used in medical contexts to describe procedures or treatments that occur outside the patient's body. For example, kidney dialysis is an extra corporeal procedure because the blood is filtered outside of the body.
Regarding the second question, the lining of body cavities that are exposed to the external environment is called mucosa. The mucosa is a membrane that lines various cavities in the body and covers the surface of internal organs. It is involved in absorption and secretion, providing a protective barrier to the underlying tissues.