If the sequence of one strand of DNA is 5' A T G C A T C G 3' find the sequence of complementary strand in ` 5 to 3` direction.

Options

A. TAC GT AG C
B. C G AT G C A T
C. AT G C A T C G
D. AT C G TA C G

Answer

To find the sequence of the complementary strand of DNA in the 5' to 3' direction for the given strand 5' A T G C A T C G 3', follow these steps:

### Step 1: Identify the complementary base pairs
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)

### Step 2: Write down the complementary bases
Given the sequence of one strand:
5' A T G C A T C G 3'

We will find the complementary bases for each nucleotide:
- A (Adenine) pairs with T (Thymine)
- T (Thymine) pairs with A (Adenine)
- G (Guanine) pairs with C (Cytosine)
- C (Cytosine) pairs with G (Guanine)
- A (Adenine) pairs with T (Thymine)
- T (Thymine) pairs with A (Adenine)
- C (Cytosine) pairs with G (Guanine)
- G (Guanine) pairs with C (Cytosine)

### Step 3: Write the complementary sequence in the 3' to 5' direction
Now, we can write the complementary sequence based on the pairs identified:
3' T A C G T A G C 5'

### Step 4: Reverse the sequence to obtain the 5' to 3' direction
Since the question asks for the complementary strand in the 5' to 3' direction, we need to reverse the order of the complementary bases:
5' C G A T A C G T 3'

### Final Answer
The sequence of the complementary strand in the 5' to 3' direction is:
**5' C G A T A C G T 3'**