DNA calculation nucleotides

Question

1078 cytidylic nucleotides in DNA molecules are 22% from general amount of nucleotides. Define:

-How many A, G, T- nucleotides are there in this DNA fragment?

-What is the length of this fragment?

-What is the mass of this fragment?

-What is the mass of corresponding fragment in mRNA molecules?'

-How many amino acids will be present in the polypeptide strand if 350 nucleotides in mRNA are introns?

Answer 1

I'd be happy to get you started in the right direction, but I don't have the schedule to answer all of the questions for you at the moment.

If 22% of the Cytidylic nucleotides is 1,078, then there are 4,900 total nucleotides. (22% of 4900 is 1,078).

Because cytosine pairs with guanine, you also have 1,078 G nucleotides.

This leaves you with 56% of nucleotides unaccounted for. Because Adenine binds with Thymine, you will have 28% A nucleotides and 28% T nucleotides. 28% of the total number (4,900) is 1,372. Therefore, you will have 1,372 A nucelotides and 1,372 T nucleotides.

Length is calculated by the following: Number of base pairs multiplied by the distance between to consecutive pairs (usually 0.34nm)

Each pair (A-T) and (G-C) is one base pair. therefore, using our numbers above, there are 1,372 A-T pairs and 1,078 G-C Pairs. 1,372 + 1,078 equals: 2,450

2,450bp multiplied by .34nm equals: 833

The mass of a dna fragment is calculated by multiplying its length by 650 (one bp is equal to 650 daltons).

833 multiplied by 650 equal: 541,450 daltons

Hope this helps!