TeXes Science Practice Test

What role do mesenteries play in the anatomy of vertebrates?

1. They separate organs from the thoracic cavity

2. They suspend organs in fluid-filled cavities

3. They form the outer protection of body cavities

4. They attach muscles to the skeleton

The correct answer is: They suspend organs in fluid-filled cavities

Mesenteries serve a crucial role in vertebrate anatomy by suspending organs within fluid-filled cavities, such as the abdominal cavity. This supportive structure not only helps maintain the positions of various organs but also provides pathways for blood vessels, nerves, and lymphatics to reach the organs. The mesenteries create an environment where organs can move slightly during digestion and other bodily functions without becoming tangled or causing damage. The other choices highlight functions that are not directly associated with mesenteries. For example, while mesenteries do provide some separation between organs and the walls of body cavities, they do not primarily function to separate organs from the thoracic cavity. Additionally, mesenteries are not responsible for forming outer protective layers for body cavities, as this function is fulfilled by other structures such as the peritoneum. Lastly, mesenteries do not attach muscles to the skeleton; that role is performed by tendons and ligaments. Understanding the specific role of mesenteries clarifies their importance in maintaining organ placement and function within vertebrate anatomy.