After completing Problem 17, carefully draw a line below the mRNA to represent its polypeptide product in accurate alignment with the mRNA. Label the N-terminal and C-terminal ends of the polypeptide. Carefully draw two lines above and parallel to the mRNA, and label them 'coding strand' and 'template strand.' Locate the DNA promoter sequence. Identify the locations of the  nucleotide and of a transcription termination sequence.

Verified step by step guidance

1. Identify the mRNA sequence from Problem 17 and note its 5' to 3' direction.
2. Draw a line below the mRNA sequence to represent the polypeptide chain, aligning each codon with its corresponding amino acid.
3. Label the N-terminal (amino end) at the start of the polypeptide and the C-terminal (carboxyl end) at the end.
4. Draw two lines above the mRNA: one for the 'coding strand' (5' to 3') and one for the 'template strand' (3' to 5').
5. Locate the DNA promoter sequence upstream of the mRNA start site and identify the transcription termination sequence downstream.

Key Concepts

Transcription

Transcription is the process by which the genetic information encoded in DNA is copied into messenger RNA (mRNA). This occurs in the nucleus of eukaryotic cells, where RNA polymerase binds to the promoter region of a gene, unwinding the DNA and synthesizing a complementary RNA strand. Understanding transcription is crucial for accurately representing the relationship between DNA and mRNA in the context of gene expression.

Polypeptide Structure

A polypeptide is a chain of amino acids linked by peptide bonds, which is synthesized during translation based on the sequence of codons in mRNA. The polypeptide has distinct ends: the N-terminal (amino end) and the C-terminal (carboxyl end), which are important for its function and folding. Recognizing these structural features is essential for accurately labeling the polypeptide product derived from the mRNA.

DNA Strands

In the context of transcription, DNA consists of two strands: the coding strand and the template strand. The coding strand has the same sequence as the mRNA (except for thymine being replaced by uracil), while the template strand is complementary to the mRNA and serves as the actual template for RNA synthesis. Identifying these strands is vital for understanding how genetic information is transcribed and how the promoter and termination sequences function in this process.