Which of the following structures are present in both prokaryotic and eukaryotic cells? Plasma membrane, Golgi apparatus, DNA, lysosomes and peroxisomes, cytoplasm and Mitochondria contain their own DNA (circular) and have a double membrane. What explanation for this observation can you come up with? (Hint 1: Where else do we see circular DNA?) (Hint 2: What do you know about the relative age of eukaryotic cells?)