What would the syllable c denote in the term cDNA used in genetic engineering?

Options

A. Copy
B. Complementary
C. Both (1) and (2)
D. Common

Answer

To answer the question about what the syllable "c" denotes in the term cDNA used in genetic engineering, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding cDNA**: The term cDNA stands for "complementary DNA." This is a crucial concept in genetic engineering.

2. **Origin of cDNA**: cDNA is synthesized from RNA. The process involves using an enzyme called reverse transcriptase, which converts RNA into DNA.

3. **Process of Synthesis**:
- **Reverse Transcriptase**: This enzyme creates the first strand of DNA from the RNA template, forming a DNA-RNA duplex.
- **RNAase H**: This enzyme degrades the RNA strand in the DNA-RNA duplex.
- **DNA Polymerase**: This enzyme synthesizes the second DNA strand, complementing the first strand.
- **DNA Ligase**: This enzyme joins the DNA fragments together to form a complete double-stranded DNA molecule.

4. **Complementarity**: The term "complementary" refers to the fact that the DNA synthesized is complementary to the original RNA strand. This is why it is called complementary DNA (cDNA).

5. **Conclusion**: Therefore, the syllable "c" in cDNA denotes "complementary."

### Final Answer:
The syllable "c" in the term cDNA used in genetic engineering denotes "complementary."

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