"Asternal" is an adjective that refers to the absence or lack of a sternum, which is a flat bone located in the center of the chest. Derived from the prefix "a-" meaning "without" or "not," and "sternal" pertaining to the sternum, this term is typically used in the context of biology, anatomy, and zoology.
In human anatomy, the sternum is an essential component of the rib cage, providing structural support and protection to vital organs like the heart and lungs. However, certain medical conditions or developmental abnormalities may result in the absence or incomplete formation of the sternum, leading to the asternal condition. This condition can have varying degrees of severity, ranging from a partial or malformed sternum to a complete absence.
In zoology, particularly in the study of animals such as fishes, reptiles, and birds, "asternal" can describe species or individuals belonging to certain taxonomic groups that lack a sternum. Since the sternum is a characteristic feature of mammals, the asternal condition can be observed in non-mammalian species.
Overall, "asternal" refers to the lack or absence of a sternum in both human and non-human contexts, signifying a particular anatomical or developmental characteristic.
