What makes mitochondrial DNA useful as a molecular clock?

It is only found in select organisms, making it easier to compare relationships between species that have it.

A large portion of the DNA ring is not vital to structure or function, allowing it to accumulate neutral mutations.

Its rate of mutation increases over time as organisms continue to evolve and differentiate from each other.

A slow mutation rate makes it useful for determining evolutionary relationships between ancient species.

Question

What makes mitochondrial DNA useful as a molecular clock? 

 It is only found in select organisms, making it easier to compare relationships between species that have it. 

 A large portion of the DNA ring is not vital to structure or function, allowing it to accumulate neutral mutations. 

 Its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. 

 A slow mutation rate makes it useful for determining evolutionary relationships between ancient species.

kayne · Answer

Hi @DarkFairyTale ! Welcome to OpenStudy. Refer to this paper for more pieces of information: [ http://www.pnas.org/content/76/4/1967.full.pdf ] Check out this pdf as well: http://ase.tufts.edu/chemistry/hhmi/documents/Protocols/Maternal%20Ancestry_Introduction_Reworked_Aug_25_2011.pdf Maybe they could help you out.

anonymous · Answer

This was actually very helpful, hmm.

kayne · Answer

Great then :)

anonymous · Answer

It's a lot of reading though. guess i have to get started.

kayne · Answer

It isn't really. Happy reading :)

anonymous · Answer

Lol thanks.

anonymous · Answer

So it's not, A slow mutation rate makes it useful for determining evolutionary relationships between ancient species.

kayne · Answer

Definitely isn't cause it has a faster mutation rate than nuclear DNA and the one thing which makes it interesting to determine evolutionary change and trace back ancestors is that it comes from the maternal cell only.

anonymous · Answer

I'm guessing it's not the second one, isn't that the purpose of mitochondria DNA?

kayne · Answer

You mean the second option is the purpose of mtDNA?

anonymous · Answer

but, doesn't it control the function and replication of other mt? then how come it says it's not vital?

kayne · Answer

Well, actually, personally.. I wouldn't go with the second option cause I don't think that it's right. Having a small genome size I don't think that it would have a part which wouldn't be vital for the mt. I would go with the third option by elimination. What do you think?

anonymous · Answer

that makes sense actually, wow your good at this. thanks :)

kayne · Answer

You're welcome @DarkFairyTale :)

kayne · Answer

By the way, the question asked you about the molecular clock, so, another point against the second option. http://en.wikipedia.org/wiki/Molecular_clock

anonymous · Answer

your covering all bases lol thanks