Question

underline the section that matches the nerve protein.

1. reflection:
2. did both proteins come from the same dna strand?
3. why doesnt a muscle cell make the nerve protein?

Explanation:

Reflection Questions:

1. Did both proteins come from the same DNA strand?

In eukaryotic cells, a single DNA strand can have multiple genes, and different proteins can be transcribed from different regions (genes) of the same DNA strand. Also, through processes like alternative splicing, different proteins can be produced from the same gene (hence same DNA strand region). So, it is possible for two proteins to come from the same DNA strand, especially if they are encoded by different genes on that strand or via alternative splicing of a single gene's transcript.

Cells undergo cell differentiation and have gene regulation (specifically, transcriptional regulation, post - transcriptional regulation, etc.). Muscle cells and nerve cells have the same genome but different sets of genes are expressed (or “turned on”) in each cell type. Muscle cells express genes related to muscle function (like actin, myosin), while nerve cells express genes related to nerve function (including nerve - specific proteins). This is due to different transcription factors, epigenetic modifications, and regulatory mechanisms that control which genes are transcribed and translated in each cell type. So, muscle cells do not express the genes required to make the nerve protein because their gene expression program is specialized for muscle - related functions.

Answer:

It is possible. A single DNA strand contains multiple genes, and different proteins can be transcribed from different genes on the same strand. Also, alternative splicing of a gene’s transcript (from the same DNA strand) can produce different proteins. So, two proteins may come from the same DNA strand.

2. Why doesn’t a muscle cell make the nerve protein?