What is DNA?
Deoxyribonucleic acid (DNA) is a complex molecule that encodes all the genetic information that is necessary to develop all the living organisms. There is nuclear Deoxyribonucleic acid, which is located in the cell nucleus and there is also mitochondrial-Deoxyribonucleic acid or mtDNA which is located in the mitochondria.
Deoxyribonucleic acid must exists in a condensed, chromatin form in order to fit inside a cell nucleus. Since Deoxyribonucleic acid is negatively changed due to it’s phosphate groups, it attracts the positively charged Histone octamer (2 sets of H2A, H2B, H3 & H4) to form a nucleosome “bead”. Octamer subunits consist primarily of Lysine and Arginine amino acids, which are positively charged. H1 Ties nucleosome beads together in a string.
Deoxyribonucleic acid holds information as a code that are made of four different chemical bases. Thymine (T), Adenine (A), Guanine (G) and Cytosine (C). These bases pain up with each other (A with T) through 2 hydrogen bonds and (C with G) through 3 hydrogen bonds. The 3 hydrogen bonds in C-G make them stronger than the A-T bond.
This tutorial on DNA has been provided by: Khan Academy