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#bio
short tandem repeat
#card/reverse repeating patterns found in dna. Using the number of instances that a small sample is repeated can be used for dna analysis in order to figure out crime scenes and such. ^1654056403856
replicating dna
semiconservative model
idk, seems like the legit way that dna is actually replicated, as opposed to the conservative model and the dispersive model. looks like !
primase ::: molecule primer, initiates the construction of new dna. creates rna primer. ^1654057167325 DNA polymerase ::: an enzyme for making dna. uses primer and parental dna to match up new dna nucleotides to make a new dna strand. ^1654057167331 helicase ::: unzips both sides of the dna molecule. You can only go from 5' to 3'. only in one direction.
- leading strand goes in the right direction
- lagging strand has to go back and forth, since it's backwards.
thermal cycler
ingredients for lab dna reading in a thermal cycler.
- h20
- dna
- primer
- nucleotides
- polymerase
the cycler heats the dna up to get it seperate, then cools it down in a cylce that does a great job of breaking stuff up and letting you exponentially copy the dna. You can just sequence the dna like in STRs, or you can put it in an agar gel, and turn on an electric charge. Short fragments go fast, long dna goes slow.
dna difference detection.
You have to cut the dna into different fragments by using a tool to cut at molecular palindromes. !
Some dna is cut differently, like so:!
You'll see dna like this: !
You can thus see that the dna is different. The suspect has a really short piece that the crime scene dna doesn't have.
The scissors are called restriction enzymes. The analysis used is called RFLP ::: Restriction Fragment Length Polymorphisms, you're looking for palindromes, where either side of the dna is the reverse of the other.