Which of the following statements are TRUE regarding the mitochondrial genome? Selected C. Its evolutionary clock "ticks" much faster than nuclear DNA. Answers: A. It has a strict codon usage. B. Its genes are present at a lower copy number per cell than nuclear DNA. C. Its evolutionary clock "ticks" much faster than nuclear DNA. D. None of these statements are true about mitochondrial DNA. E. In humans, it contains a high percentage of noncoding DNA.