Testüregének

Testüregének is a Hungarian term that translates to "body cavity" in English. It refers to any fluid-filled space within a multicellular organism. In biological contexts, this term often distinguishes between different types of body cavities based on their location and the organs they contain.

In vertebrates, the two main body cavities are the dorsal cavity and the ventral cavity. The dorsal cavity is located at the back of the body and is further divided into the cranial cavity, which houses the brain, and the vertebral cavity, which contains the spinal cord. The ventral cavity is located at the front of the body and is divided by the diaphragm into the thoracic cavity (containing the heart and lungs) and the abdominopelvic cavity (containing digestive organs, reproductive organs, and the bladder).

In invertebrates, the term can refer to a coelom, which is a true body cavity completely lined by mesoderm. Some invertebrates have a pseudocoelom, a partially lined body cavity, while others, like flatworms, have no body cavity at all. The presence and type of body cavity are important characteristics in the classification and study of animal life. The fluid within these cavities often plays roles in protecting organs, facilitating movement, and transporting substances.