In the DNA strand undergoing transcription has a following base pair sequence. What would be the sequence of mRNA formed from this strand?
`"3' GAT CTT AGC GGG AAT TCG 5'"`

Options

A. 5' GAU CUU AGC GGG AAU UCG 3'
B. 5' CAU GAA UGC CCC UUA AGC 3'
C. 5' CUA GAA UCG CCC UUA AGC 3'
D. 3' CUA GAA UGG CCC UUA AGC 5'

Answer

To determine the mRNA sequence formed from the given DNA strand, we need to follow the transcription process, where the DNA template strand is used to synthesize mRNA. The DNA sequence provided is:

**3' GAT CTT AGC GGG AAT TCG 5'**

### Step-by-Step Solution:

1. **Identify the Template Strand**:
The given DNA sequence is in the 3' to 5' direction. During transcription, the mRNA is synthesized in the 5' to 3' direction, complementary to the DNA template strand.

2. **Complementary Base Pairing**:
In RNA, adenine (A) pairs with uracil (U) instead of thymine (T), which is found in DNA. The base pairing rules are as follows:
- A (Adenine) pairs with U (Uracil)
- T (Thymine) pairs with A (Adenine)
- C (Cytosine) pairs with G (Guanine)
- G (Guanine) pairs with C (Cytosine)

3. **Transcribing the DNA Sequence**:
We will transcribe the DNA sequence from 3' to 5' into mRNA from 5' to 3':
- DNA: 3' GAT CTT AGC GGG AAT TCG 5'
- mRNA: 5' CUA GAA UCG CCC UUA AGC 3'

4. **Final mRNA Sequence**:
The final mRNA sequence synthesized from the given DNA template strand is:
**5' CUA GAA UCG CCC UUA AGC 3'**