Answer:
1. Sample 1= A=32, T=32, G=18, C=18
Sample 2:
2. Chargaff rule (A=T and G=C)
3. Sample 2
Explanation:
Sample 1= Adenine percentage= 32%
According to the Chargaff rule, thymine percentage in this sample DNA would be= 32%
Sum total of adenine and thymine in sample 1= 32 + 32 =64%
Sum total of GC content in the sample 1= 100-64= 36
Percentage of guanine bases in sample 1= 36/2=18%
Percentage of cytosine bases in sample 1= 18%
Sample 2
Adenine percentage= 17%
According to the Chargaff rule, thymine percentage in this sample DNA would be= 17%
Sum total of adenine and thymine in sample 2=17 + 17 = 34%
Sum total of GC content in the sample 2= 100-34= 66
Percentage of guanine bases in sample 2= 66/2=33%
Percentage of cytosine bases in sample 2= 33%
2. Percentage of adenine= percentage of thymine
Percentage of guanine= percentage of cytosine
3. DNA from sample 2 is from the bacterial living in hot water spring since it has a higher percentage of GC (66%) than sample 1 (36%). The GC bases have three hydrogen bonds between them and are relatively more stable base pairs than the AT pairs each with two hydrogen bonds.
