OCR Biology A2- an introduction to genetic engineering

on page 174 of the OCR biology book, does anyone know what they mean when they say 'vectors often have to contain regulatory sequences of DNA'?

The bit in the book on replica plating should elaborate on this


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thank you, I've read the bit on replica plating. I don't understand what they mean when they say 'original plasmid ' though? is this plasmid from the E.coli?

Yeah - so the ones they picked to be engineered

on page 174 of the OCR biology book, does anyone know what they mean when they say 'vectors often have to contain regulatory sequences of DNA'?

You should know that regulatory sequence means "a series of DNA nucleotides that regulate the expression of a gene". Vectors have to contain these, so that the gene you want is expressed more frequently especially since the cells injected with this DNA die; and new cells are made which do not contain this gene (not sure if I phrased it correctly).

Edit: it also needed to prevent further replication, causing development of tumours.

Why would two different antibiotics be required? Surely you could just put the bacteria on the tetracycline, the bacteria that die are the ones with insulin, so they are the ones you want. I don't see the need for the ampicillin.

to see if the bacteria have taken up any of the plasmids at all..
some bacteria won't take up the plasmids so its just to differentiate between those that do and those that don't.
What i don't understand is why you use tetracycline cause that will just kill the bacteria containing insulin and thats the one we want so why would u want to kill it?