DNA Structure and Replication Flashcards
What is DNA and where is it found?
DNA is a double standed molecule which:
-in eurkaryotic cells is found as linear and bound to histones in chromosomes in the nucleus as well as found in the mitochondria and chloroplasts
-in prokaryotic cells is found as circular and unbound in the cytosol
What is the general structure of DNA?
DNA consists of two antiparallel strands of nucleotides wound together into a double helix. These nucleotide units are made up of a sugar, phosphate group and nitrogeneous base. The bases are A, T, G, C with AT and GC being the complementary pairs bonded by weak hydrogen bonds.
What is the role of helicase and DNA polymerase in the process of DNA replication?
In DNA replication, helicase unwinds the DNA double helix by breaking the hydrogen between the complementary bases, separating the strands. DNA polymerase then replicates the DNA template strand to act as the new pair synthesising the 5’ to 3’ strand from the 3’ to 5’.
