It has now been established (according to the Cambridge A level text book) that
organisms form a symbiotic partnership, typically by one engulfing the other – a process known as endosymbiosis. Dramatic evolutionary changes result. The classic examples, now confirmed by later work, were the suggestions that mitochondria and chloroplasts were originally free-living bacteria (prokaryotes) which invaded the ancestors of modern eukaryotic cells (cells with nuclei).
It also states that
It was also discovered in the 1960s that mitochondria and chloroplasts contain small, circular DNA molecules, also like those found in bacteria
The DNA and ribosomes of mitochondria and chloroplasts are still active and responsible for the coding and synthesis of certain vital proteins, but mitochondria and chloroplasts can no longer live independently.
So my question is:
Is this DNA found in the mitochondria and chloroplasts coded for in the host's (animal's or plant's) DNA.
If not are there fully formed mitochondria and/or chloroplasts in all gametes (obviously chloroplasts only in the plant gametes) which were transferred directly from the parent who had them transferred directly from their parent and so on?
If so are all the mitochondria and chloroplasts of one type identical in a organism? Are they almost identicle in families (of organisms not the classifictaion Family)?