How can DNA be copied and why is this neccessary?

Question

full explanation- long answer in simple language.
Thanks

Answer 1

DNA is the code to make proteins, which are what make up who we are. The central dogma of biology is DNA->RNA->Protein. DNA is copied into messenger RNA (mRNA). This mRNA is taken from the nucleus toa ribosome to be turned into protein by way of transfer RNA (tRNA). tRNA's have an anticodon, which is 3 bases that match up against a codon (3 bases on a mRNA strand). Each tRNA carries on it an amino acid, when the anticodon meets the codon, the amino acid is attached to the protein chain. After the whole chain is made, the protein goes off to fulfill the duty it was made for (muscles, repair, etc)

Answer 2

DNA must be copied for organisms to reproduce. The simplest is the circular, double-stranded DNA of bacteria. Something gets between the strands and unwinds them a bit. A polymerase enzyme makes a copy by stitching nucleic acids together to make a new complimentary strand. If that sounds like a contortion, it is. The way that fluoroquinone (Cipro) antibiotics work is to screw up that unwinding. The bacterial genome becomes so contorted that it just sits there and dies. Humans don't have circular genomes, so they're unaffected.

Answer 3

DNA is a double helix. An enzyme called DNA Polymerase, seperates the two strands of the helix, and also aids both strands in forming complimentary bases. After all is done, both strands are identical to the original one, unless a mutation occurs. Have a look: http://bio.usuhs.mil/dna_replication2.gif
DNA replication is important for cell division - Mitosis and Meiosis.

Answer 4

Check out this web site, it awesome for explaining things in lay terms

http://science.howstuffworks.com/dna2.htm