What primitive internal feature remains unossified in the White Sturgeon's backbone?
Answer
A persistent, unossified notochord
Although the White Sturgeon is classified as a bony fish (Osteichthyes), its internal skeletal structure retains a significant amount of cartilage. A key primitive feature is the presence of a persistent notochord within the backbone. The notochord is the flexible rod that provides primary support in all vertebrate embryos, but it is typically replaced entirely by bone during development in higher, more evolutionarily recent fish species. The persistence of this unossified notochord contributes to the overall flexibility of the sturgeon’s body plan, contrasting with the more rigidly ossified skeletons of many modern bony fish.
Related Questions
To which geological period does the White Sturgeon fossil record extend?What is the dermal armor structure replacing true scales on the White Sturgeon?What primitive internal feature remains unossified in the White Sturgeon's backbone?What aids the White Sturgeon's bottom-feeding by locating food on dark bottoms?Which geographic extremes define the native range of the White Sturgeon in the Pacific basin?What life history strategy characterizes the White Sturgeon's approach to reproduction?What term describes the White Sturgeon's ability to migrate between salt and fresh water?What anthropogenic pressure negates the White Sturgeon's ancient defensive adaptations?Approximately how old must female White Sturgeon be to reach sexual maturity?To which biological family do White Sturgeons belong, according to the text?