Question

optional: there was extra paper. if you feel this would be helpful, use this as a study tool.
word bank:

• trna
• transcription
• peptide bond
• mature mrna
• h - bonds
• trna anticodon
• translation
• phosphodiester bond
• ribosome
• rna processing
• amino acid
• pre - mrna
• dna molecule

add more information along the arrows to help explain the processes. what happens to the polypeptide chain once it leaves the ribosome? where would a mutation occur?

Explanation:

1. Labeling the diagram (from top to bottom, left to right):

• Top DNA structure: DNA molecule; labeled arrow points to complementary base pairs held by H-bonds
• First downward arrow/process: transcription; produces pre-mRNA
• Second downward arrow/process: RNA processing; adds 5' cap (labeled arrow) and poly-A tail, resulting in mature mRNA
• Mature mRNA moves to cytosol; next process is translation
• The large complex holding mRNA is Ribosome
• The cloverleaf structures are tRNA, each carrying an amino acid (labeled arrow pointing to Thr)
• tRNA's matching sequence to mRNA is tRNA anticodon
• The links between amino acids (Ala-Gly) are peptide bond
• mRNA backbone is held together by phosphodiester bond

1. Post-ribosome polypeptide fate: After leaving the ribosome, the polypeptide chain undergoes folding into its 3D functional shape (primary → secondary → tertiary → quaternary structure), may be modified (e.g., adding chemical groups), and is transported to its target cellular location to act as a functional protein.
2. Mutation location: Mutations occur in the DNA molecule (in the nucleus), during DNA replication or exposure to mutagens. Changes in DNA sequence alter the mRNA produced, which can then change the resulting polypeptide/protein.

Answer:

Diagram Labels (matching word bank):

• DNA molecule (top double helix)
• H-bonds (arrow to DNA base pairs)
• transcription (first downward process arrow)
• pre-mRNA (first RNA strand)
• RNA processing (second downward process arrow)
• 5' cap (arrow to mRNA end)
• mature mRNA (processed RNA strand)
• translation (process arrow to ribosome step)
• Ribosome (complex holding mRNA)
• tRNA (cloverleaf structures)
• amino acid (arrow to Thr on tRNA)
• tRNA anticodon (tRNA's matching sequence to mRNA)
• peptide bond (link between Ala and Gly)
• phosphodiester bond (mRNA backbone links)

Additional Questions:

1. Once the polypeptide chain leaves the ribosome, it folds into a specific 3D structure (with help from chaperone proteins in some cases), may undergo post-translational modifications, and is transported to its correct cellular location to function as a protein.
2. A mutation would occur in the DNA molecule (within the nucleus of the cell), altering the nucleotide sequence that serves as the template for transcription.