The sequence of nitrogen bases in a portion of a DNA segment of a template strand was AAT GCT TAG GCH. What will be the sequence of nitrogen bases in the corresponding region of the transcribed mRNA ?

Options

A. UUT CGT TUC CGH
B. AAT GCT TAG GCA
C. UUA CGA AUG CGU
D. TTA CGA ATC CGT

Answer

To determine the sequence of nitrogen bases in the corresponding region of the transcribed mRNA from the given DNA template strand, we need to follow these steps:

### Step 1: Identify the DNA Template Strand
The given DNA template strand is:
**AAT GCT TAG GCH**

### Step 2: Understand Base Pairing Rules
In DNA, the base pairing rules are as follows:
- Adenine (A) pairs with Thymine (T)
- Thymine (T) pairs with Adenine (A)
- Cytosine (C) pairs with Guanine (G)
- Guanine (G) pairs with Cytosine (C)

However, when transcribing DNA to mRNA, Thymine (T) is replaced by Uracil (U) in RNA.

### Step 3: Transcribe the DNA Sequence to mRNA
Now, we will transcribe the DNA sequence to mRNA using the base pairing rules, keeping in mind the substitution of Uracil for Thymine.

1. **AAT**:
- A pairs with U
- A pairs with U
- T pairs with A
- Result: **UUA**

2. **GCT**:
- G pairs with C
- C pairs with G
- T pairs with A
- Result: **CGA**

3. **TAG**:
- T pairs with A
- A pairs with U
- G pairs with C
- Result: **AUC**

4. **GCH**:
- G pairs with C
- C pairs with G
- H is not a standard base in DNA; assuming it is a typo for T, we will treat it as T.
- T pairs with A
- Result: **CAU** (if we treat H as T)

### Step 4: Combine the mRNA Segments
Now, we combine all the transcribed segments to get the complete mRNA sequence:
- mRNA Sequence: **UUA CGA AUC CAU**

### Final Answer
The sequence of nitrogen bases in the corresponding region of the transcribed mRNA is:
**UUA CGA AUC CAU**

---