Question

If R = any purine, Y = any pyrimidine, and N = any nucleotide, what is the probability of finding the sequence 5′ GRANTY 3′ in any molecule of DNA? Assume nucleotides are in equal percentages.

Answer 1

The probability of finding the sequence 5′ GRANTY 3′ in any molecule of DNA is 6.25%.

Step-by-step explanation:

The probability of finding the sequence 5′ GRANTY 3′ in any molecule of DNA can be calculated by considering the individual probabilities of each base in the sequence. Since the sequence contains one purine (G) and one pyrimidine (T), we need to consider the probabilities of finding these bases in DNA.

According to Chargaff's rule, the amount of guanine (G) in DNA is approximately equal to the amount of cytosine (C), and the amount of adenine (A) is approximately equal to the amount of thymine (T). Therefore, the probability of finding G and T in DNA is the same.

Assuming nucleotides are in equal percentages, the probability of finding G or T in a DNA molecule is 25% each. Multiplying these probabilities together gives us the probability of finding the sequence 5′ GRANTY 3′ in any molecule of DNA, which is 0.25 * 0.25 = 0.0625 or 6.25%.