What is the complementary `m-RNA` sequence for the DNA segment AATCAGTT?

Options

A. AAUCAGUU
B. CCAUCGAA
C. AACUGAUU
D. UUAGUCAA

Explanation

To find the complementary mRNA sequence for the DNA segment AATCAGTT, we need to follow these steps:

### Step-by-Step Solution:

1. **Identify the DNA Sequence**: The given DNA sequence is AATCAGTT.

2. **Understand Base Pairing Rules**: In DNA, the base pairing rules are:
- 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 we transcribe DNA to mRNA, Thymine (T) is replaced by Uracil (U):
- Adenine (A) pairs with Uracil (U)
- Uracil (U) pairs with Adenine (A)
- Cytosine (C) pairs with Guanine (G)
- Guanine (G) pairs with Cytosine (C)

3. **Transcribe the DNA Sequence**: Now we will replace each base in the DNA sequence with its complementary RNA base:
- A (Adenine) → U (Uracil)
- A (Adenine) → U (Uracil)
- T (Thymine) → A (Adenine)
- C (Cytosine) → G (Guanine)
- A (Adenine) → U (Uracil)
- G (Guanine) → C (Cytosine)
- T (Thymine) → A (Adenine)
- T (Thymine) → A (Adenine)

4. **Write the mRNA Sequence**: Putting it all together, we get the mRNA sequence:
- UUA GUC AA

5. **Final mRNA Sequence**: The complementary mRNA sequence for the DNA segment AATCAGTT is:
- UUA GUC AA