Genomic DNA from a mouse is isolated, fragmented, and denatured into single strands. It is then mixed with mRNA isolated from the cytoplasm of mouse cells. The image represents an electron micrograph result showing the hybridization of single-stranded DNA and mRNA.
What term best identifies the nucleic acid region indicated by the 'c' pointer?

Verified step by step guidance

1. Understand the context: The problem involves hybridization of single-stranded DNA (ssDNA) and mRNA. Hybridization occurs when complementary sequences of nucleic acids (DNA and RNA) bind to each other. The electron micrograph shows regions where this binding has occurred.
2. Identify the components: In the hybridization process, mRNA binds to its complementary DNA sequence. However, not all regions of the DNA may have corresponding mRNA. Some regions of the DNA may not be transcribed into mRNA, such as introns in eukaryotic genes.
3. Focus on the 'c' pointer: The 'c' pointer likely indicates a region of the DNA that does not hybridize with the mRNA. This could represent a non-coding region, such as an intron, which is present in the DNA but spliced out of the mRNA during RNA processing.
4. Recall key concepts: In eukaryotes, genes are transcribed into pre-mRNA, which contains both exons (coding regions) and introns (non-coding regions). Introns are removed during RNA splicing, so they are absent in the mature mRNA. When hybridized with DNA, these intronic regions form loops because they do not have complementary sequences in the mRNA.
5. Conclude the term: Based on the description, the region indicated by the 'c' pointer is likely an intron, as it represents a non-coding sequence in the DNA that does not hybridize with the mRNA.

Key Concepts

Hybridization

Hybridization refers to the process where complementary nucleic acid strands, such as DNA and RNA, bind together to form a stable double-stranded structure. In this context, the single-stranded DNA from the mouse genome pairs with the mRNA, allowing researchers to study gene expression and the specific regions of the genome that correspond to the mRNA.

cDNA

cDNA, or complementary DNA, is synthesized from an mRNA template through the action of the enzyme reverse transcriptase. This process allows researchers to create a DNA version of the mRNA, which can then be used for various applications, including cloning, sequencing, and studying gene expression. The 'c' pointer in the question likely indicates a region of cDNA formed during hybridization.

Electron Micrography

Electron micrography is a technique that uses a beam of electrons to create high-resolution images of biological specimens. This method is particularly useful for visualizing the fine details of cellular structures and molecular interactions, such as the hybridization of DNA and RNA. The resulting images can provide insights into the spatial arrangement and interactions of nucleic acids within the cell.