Of all possible DNA nucleotide sequences, what sequence of base pairs would dissociate most easily into single strands if the DNA duplex were heated gently?
A sequence with only A and T in it. A binds to T with two hydrogen bonds. G binds to C with three hydrogen bonds. The bonding between an A and a T is weaker, and more easily broken, than between a G and a C.
lier
To determine the DNA nucleotide sequence that would dissociate most easily into single strands when heated gently, we need to consider the stability of the DNA duplex. The stability of the DNA duplex is primarily determined by the strength of hydrogen bonding between the complementary base pairs.
In DNA, the base pairs are adenine (A) with thymine (T), and cytosine (C) with guanine (G). Adenine and thymine form two hydrogen bonds, while cytosine and guanine form three hydrogen bonds. Therefore, the higher the percentage of G-C base pairs within a DNA sequence, the more stable the duplex will be.
Conversely, a DNA sequence with a lower percentage of G-C base pairs will be less stable and more prone to dissociating into single strands when subjected to gentle heating. This is because the weaker hydrogen bonding between A-T base pairs is easier to break compared to the stronger hydrogen bonding between G-C base pairs.
Hence, to find the DNA nucleotide sequence that would dissociate most easily, we look for a sequence with a low percentage of G-C base pairs. For example, a DNA sequence with a high proportion of adenine (A) and thymine (T) nucleotides would have a lower stability and would likely dissociate more easily when heated gently.
It's important to note that the length and overall arrangement of the DNA sequence can also affect its stability. However, considering only the base pair composition, a DNA sequence with a low percentage of G-C base pairs would typically have relatively weaker stability and would dissociate more easily into single strands when gently heated.