Question

What is different between the type of DNA scientists use to clone and propagate genes in bacteria such as E. coli, and the DNA that is present in a plant cell’s nucleus?

Answer 1

A plant cell’s nucleus has double stranded DNA. Two strands of DNA are wound with each other in the form of helix.

E. coli has long, single molecule of double stranded, helical, supercoiled DNA called it’s chromosome. Other single stranded DNA molecules are present within the cell called plasmid DNA. Plasmid DNA replicate separately from the chromosome. Scientists use these plasmid DNAs to clone and propagate genes.

These plasmid molecules are isolated from a bacteria, cut , foreign part of dna is joined with it and put back in the bacteria for replication. In this way genes are amplified.

Base pairs Adenine Thymine Guanine cytosine Sugar phosphate backbone U.S. National Library of Medicine

Bacterial DNA Plasmids Q0

Recombinant DNA Gene for human growth hormone EcoRI Gene for human growth hormone Human Cell Sticky ends DNA recombination DNA insertion Bacterial Cell Bacterial chromosome EOORI es ve Bacterial cell for containing gene for human growth hormone Plasmid