The word "Presternum" is spelled as [priːˈstɜːnəm] in IPA phonetic transcription. The first syllable is pronounced as "pree" with a long "e" sound, the second syllable is "stern" with an "er" sound, and the last syllable is "num" with a short "u" sound. The spelling reflects the medical term which refers to a bone structure in birds that connects their breastbone and protects the vital organs. Understanding correct spelling and pronunciation of scientific terms can help in effective communication among professionals in the field.
The presternum is a bony structure located in the anterior part of the thorax of certain animals, most notably birds and reptiles. Also known as the manubrium or sternum, it serves as a crucial attachment point for the muscles involved in flying or locomotion.
The presternum is typically positioned at the base of the neck and extends downwards towards the abdomen. It consists of a series of fused bones or cartilaginous plates known as sternebrae, which provide rigidity and support to the chest region. In birds, this structure is highly specialized to withstand the forces generated during flight, aiding in the efficient transfer of energy during wingbeats.
The shape and size of the presternum vary across species, reflecting the diverse evolutionary adaptations within avian and reptilian lineages. For instance, in diving birds, the presternum may be more elongated and possess a keel-like protrusion called the carina, which strengthens the attachment of flight muscles.
Beyond its structural role, the presternum may also play a role in protecting vital organs, such as the heart and lungs, from external impacts or physical stress. Furthermore, it contributes to the respiratory system by providing support to the rib cage and facilitating the expansion and contraction of the chest cavity for breathing.
Overall, the presternum is a pivotal anatomical feature that ensures stability, mobility, and functionality of the thoracic region in birds and reptiles. Its morphological variations and adaptations reflect the different locomotor and flight capabilities across diverse taxa.
Manubrium sterni.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "Presternum" is a combination of two Latin terms: "pre" meaning "before" or "in front of", and "sternum" which refers to the breastbone or the central bone in the front of the ribcage. Therefore, a rough translation of "Presternum" could be "before the sternum" or "in front of the sternum". It is a term used in anatomy to describe the small bone located anteriorly to the sternum in certain species, such as some birds and reptiles.