A body system or tract that has an opening to the environment is always lined with:
A)a mucous membrane
B)a serous membrane
C)a columnar epithelium membrane
D)none of these, because the membrane varies by body system

Question

Quizplus · Accepted Answer

A mucous membrane lines any body system or tract that has an opening to the environment. This includes the respiratory, digestive, urinary, and reproductive tracts. The mucous membrane helps to protect the body from pathogens and other harmful substances, and it also helps to lubricate and moisten these tracts to allow for easier passage of materials.

A Body System or Tract That Has an Opening to the Environment