What is the best explanation for the observation that eukaryotes that seem superficially simple can have much larger genomes (in terms of mass or number of base pairs) than organisms that have complex anatomy, structure, or behavior?

Some organisms have a tremendous amount of non coding DNA, like repetitive sequences.

Explanation:

the best explanation for the observation that eukaryotes that seem superficially simple can have much larger genomes (in terms of mass or number of base pairs) than organisms that have complex anatomy, structure, or behavior is that SOME ORGANISMS HAVE A TREMENDOUS AMOUNT OF NON CODING DNA, LIKE REPETITIVE SEQUENCES.

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