How many different trinucleotides can be made using the DNA nucleotides?
Correct answer: D. 64
- A. 4
- B. 16
- C. 20
- D. 64
Explanation
Since there are four nucleotides and each trinucleotide consists of three bases, the total number of possible combinations is 43 = 64. However, since DNA is double-stranded and complementary, some combinations will be the reverse complement of others. For instance, the trinucleotide "ATG" would pair with "CAT" on the complementary strand. Therefore, the actual number of unique trinucleotides is half of 64, which is 32.
Last updated
About Structure of DNA
DNA structure includes nucleotides made of deoxyribose, phosphate and nitrogenous bases, arranged in two antiparallel polynucleotide strands. Questions cover the double helix, phosphodiester and hydrogen bonds, complementary base pairing between adenine and thymine and between guanine and cytosine, and the significance of major and minor grooves.
Practise Biological Molecules
1,790 free Biological Molecules MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Biology questions like this
Biology is on 6 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A biochemist isolated and purified molecules needed for DNA replication. When he added some DNA, replication occurred, but the DNA molecules formed were defective. Each consisted of normal DNA strand paired with numerous segments of DNA, a few hundred nucleotides long. What had the scientist probably left out of the mixture?
A genome is___________?
A polypeptide chain contains 120 amino acids.The number of DNA nucleotides that would be required to code for this polypeptide chain are
A section of a double-stranded DNA contains 150 nucleotides and codes for a polypeptide X.The number of amino acids in polypeptide X will be
A section of deoxyribonucleic acid (DNA) contains the following sequence of bases.The number of amino acids that the given section of DNA can code is