Question

3 Which is of the following statements best describes the structure, or makeup, of a codon?

A. A codon is a 3-letter nucleotide sequence found on the tRNA.

B. A codon is a growing polypeptide chain.

C. A codon is a gene sequence found on the DNA strand.

D. A codon is a 3-letter nucleotide sequence found on the mRNA.


4.What is true regarding genes and DNA?

A Each DNA strand contains identical genes.

B The DNA only transcribes the genes that it needs at specific times.

C Both A and B

D None of the above

Answer 1

3. D. A codon is a 3-letter nucleotide sequence found on the mRNA.

4. D None of the above

Step-by-step explanation:

3. A codon is a sequence of three nucleotides, or bases, on messenger RNA (mRNA) that corresponds with a specific amino acid or stop signal during protein synthesis. The sequence of nucleotides on the DNA (deoxyribonucleic acid) is copied, or transcribed, into a complementary sequence of nucleotides on the mRNA. The mRNA then travels to the ribosome, where the sequence of nucleotides, or codons, is read in groups of three. Each codon corresponds with a specific amino acid or stop signal, which are brought to the ribosome by transfer RNAs (tRNAs) and linked together to form a protein.

4. D None of the above