I know I'm a bit annoying as I asked similar question some time ago but it's all due to the lack of literature to research or at least I cannot find much.
Basically I performed PCR to amplify the tetracycline resistance gene from pBR322. I was given primers to use:
The gene itself is 1,191 bp long. However, I used some of the softwares to predict the product size, using the entire plasmid sequence and given primers and the predicted product size was 1,200 bp or something similar. After having performed PCR and running the gel I did notice bands located between 1000 - 1500 bp according to the DNA ladder I used.
I am not really sure if I predicted the correct size of the PCR product and whether the fact that the product is slightly bigger than gene itself means I amplified the wrong thing. Sorry for being repetitive but this is really confusing to me.