Final answer:
Noncoding DNA regions that are highly conserved across species have important functions within the cell, such as regulating gene expression and DNA packaging.
Step-by-step explanation:
Noncoding DNA regions that are highly conserved across species but do not code for proteins are believed to have important functions within the cell. While the exact purposes of all noncoding DNA regions are not fully understood, they are known to contribute to the regulation of gene expression, DNA packaging, chromosomal stability, and the production of small noncoding RNA molecules. These regions are not considered 'junk DNA' anymore due to their recognized roles in genome evolution.