Certified Instrument Specialist (CIS) 2025 Practice Exam – 400 Free Practice Questions to Pass the Exam

The peritoneum is indeed a membrane lining the abdominal cavity, serving as a crucial structure within the human body. This serous membrane not only covers the abdominal organs but also provides support and facilitates the movement of these organs during digestion and other activities.

It is composed of two layers: the parietal layer, which lines the abdominal wall, and the visceral layer, which envelops the organs themselves. This arrangement allows for a lubricated surface that reduces friction between the organs and the abdominal wall, contributing to the efficient functioning of the gastrointestinal tract.

In contrast, the other options do not accurately describe the peritoneum, as there is no surgical tool, organ in the digestive system, or laboratory procedure known by that name. Thus, identifying the peritoneum as a membrane lining the abdominal cavity captures its anatomical and physiological significance effectively.