(a) Describe this process of synthesis of fully functional mRNA in a eukaryotic cell.
(b) How in the process of mRNA synthesis different from that in prokaryotes?

Explanation

### Step-by-Step Solution

#### (a) Synthesis of Fully Functional mRNA in Eukaryotic Cells

1. **Initiation**:
- The process of mRNA synthesis begins with the recognition of a specific DNA sequence known as the promoter. In eukaryotes, the promoter contains a TATA box, which is a conserved sequence of nucleotides (TATAAA) located about 25-30 base pairs upstream of the transcription start site.
- The enzyme RNA polymerase II, which is responsible for synthesizing mRNA, binds to the promoter region with the help of various transcription factors that facilitate this binding.

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