Question

DNA is isolated from two different species. Both DNA samples are found to be the same size. One of the DNA samples has a G+C/A+T ratio of 2.0 and the other 2.5. Which DNA sample has a higher G+C content? Which sample contains the smallest number of H bonds between strands?

1) The DNA sample with a G+C/A+T ratio of 2.0 has a higher G+C content.
2) The DNA sample with a G+C/A+T ratio of 2.5 has a higher G+C content.
3) The DNA sample with a G+C/A+T ratio of 2.0 contains the smallest number of H bonds between strands.
4) The DNA sample with a G+C/A+T ratio of 2.5 contains the smallest number of H bonds between strands.

Answer 1

The DNA sample with a G+C/A+T ratio of 2.0 has a higher G+C content and contains the smallest number of H bonds between strands.

Step-by-step explanation:

The DNA sample with a G+C/A+T ratio of 2.0 has a higher G+C content. This is because the G+C/A+T ratio refers to the relative amount of Guanine (G) and Cytosine (C) compared to Adenine (A) and Thymine (T) in the DNA sample. The higher the ratio, the higher the G+C content.

As for the number of hydrogen bonds between strands, the DNA sample with a G+C/A+T ratio of 2.0 contains the smallest number of H bonds between strands. This is because each G-C base pair forms 3 hydrogen bonds, while each A-T base pair forms 2 hydrogen bonds. Therefore, a higher G+C content will result in a smaller number of H bonds between strands.