Question

1)In DNA, the designations 3' and 5' refer to the

A)carbon or nitrogen atoms on the rings of purine or pyrimidine bases.

B)cross-linking of the third and fifth carbon atoms of deoxyribose.

C)bonds that form between adenine and thymine and between guanine and cytosine.

D)bonding between purines and deoxyribose and between pyrimidines and deoxyribose.

E)carbon atoms of deoxyribose to which phosphate groups may bond.

2) Accuracy in the translation of mRNA into the primary structure of a protein depends on specificity in the

A)shape of the A and P sites of ribosomes.

B)binding of ribosomes to mRNA.

C)bonding of the anticodon to the codon.

D)ttachment of amino acids to tRNAs.

E)Both C and D are correct.

Answer 1

Answer 1:

E) Carbon atoms of deoxyribose to which phosphate groups may bond.

Explanation:

In DNA, the designations 3' and 5' refer to the carbon atoms of deoxyribose (i.e., the position of carbon atoms in the deoxyribose sugar) to which phosphate groups may bond. Thus, this is the correct answer.

Answer 2:

E) Both C and D are correct.

The accuracy in the translation of mRNA into the primary structure of a protein depends on specificity in the two factors— (i) complementary bonding of the anticodon of tRNA to the codon of the mRNA and (ii) attachment of correct amino acids to tRNAs. Thus, this is the correct answer.