Question

Imagine you have discovered a new species of bacteria. To begin your investigation of this organism, you

run an assay on the total nucleotide content of the bacterial DNA. The thymine content of DNA from
the bacterial cells is 40%. You also run an assay on the total nucleotide content of E. coli, another
species of bacterium. The thymine content of DNA from E. coli is 24%.
T/F: the DNA from your new bacterial species will denature at a higher temperature than the DNA from
E. coli.
O True
O False

Answer 1

O

Step-by-step explanation:

the answer is false

Answer 2

The new bacterial species with higher thymine content would likely have fewer guanine-cytosine pairs, which confer stability, thus it will denature at a lower temperature compared to E. coli. The statement is therefore False.

Step-by-step explanation:

The thymine content of DNA from the newly discovered bacteria is 40%, which suggests that adenine will also be 40%, based on Chargaff's rules which state that the amount of adenine (A) equals the amount of thymine (T), and the amount of cytosine (C) equals the amount of guanine (G). Given that the thymine content of DNA from E. coli is 24%, and thus adenine would also be 24%, we can infer that the proportion of guanine-cytosine pairs, which are bound by three hydrogen bonds (stronger than the two hydrogen bonds that bind adenine and thymine), is lower in the new bacterial species compared to E. coli. Therefore, the DNA of the new bacterial species would denature at a lower temperature than E. coli, because it has fewer GC pairs which confer additional stability to the DNA helix.

Thus, the correct answer to the question ‘the DNA from your new bacterial species will denature at a higher temperature than the DNA from E. coli’ would be False.