Mitochondrial dna contains a few codons that specify amino acids other than those specified by codons of nuclear dna. uses the same assortment of codons as does the dna in the nucleus. can never replicate itself because dna polymerases are not present in mitochondria. can never be transcribed or translated because rna polymerases are not in mitochondria. can never replicate itself because there are no promoter sequences to initiate transcription

I did not understand what's your question, perhaps you need more information about the mitochondria:
About the codon, it is true that the genetic code of mitochondria is different than the "universal" one: for example UGA codes for STOP in mammals chromosomes but codes a TRP in their mitochondria.

Mitochondria is always dependent on the cell regarding the materials, it means it cannot replicate it self (it replicates only during interphase), and cannot be transcribed by itself, but still independent because both chromosome and mitochondria have their own mechanisms of regulation.

Mitochondria's DNA has only one promoter (it gives only one transcript), while the chromosomal's DNA has many of them.