How could a cell replicate single stranded DNA so the daughter cells could receive an exact copy of the genes present in the original cell?
Explain why it is an advantage for DNA to have a double helix structure with paired nucleotides
It is important to understand the inner structure of a strand of DNA. DNA is like a ladder, a ladder used to climb up the side of a house, except the ladder is twisted into a spiral shape. The rungs of the ladder, the parts a person would step on, are composed of two nucleotide bases. There are only four bases, and they are adenine, guanine, cytosine, and thymine. These bases pair with each other like this: adenine to thymine; cytosine to guanine.
The DNA unwinds and splits down the middle of the "rung" part, each side serving as a template with its order of bases. RNA serves to match up with the existing base order and create a new, complementary strand of DNA that correctly pairs up with the existing template. This is how daughter cells receive their copy of the DNA from original cells.
It should also be noted that sometimes, mistakes happen in the pairing of these bases. When such mistakes occur, they are said to be mutations. Three things can happen when mutations occur: 1) some beneficial improvement, 2) a disastrous, health-harming effect, or 3) nothing at all. For most mutations, it is the third category that manifests itself.