Biology · Chromosomes and DNA
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In DNA double helix, the Thymine is paired with ________, cytosine is paired with _______
- A
Thymine ; Guanine
- B
Adenine ; Guanine
- C
Adenine ; Cytosine
- D
Adenine ; Guanine
The base pairing in DNA is specific:
Adenine (A) always pairs with Thymine (T), and Cytosine (C) always pairs with Guanine (G). So, the correct pairing for Thymine (T) is Cytosine (C).
Guanine pairs with Cytosine, not Thymine. Thymine pairs with Adenine.
This option incorrectly pairs Adenine with Guanine. Adenine pairs with Thymine.
This option correctly pairs Adenine with Thymine, but Cytosine should pair with Guanine.
The correct base pairing is Adenine (A) with Thymine (T) and Cytosine (C) with Guanine (G). Thus, the answer should be Adenine; Guanine for Thymine and Cytosine respectively.
Tagged under Biology · Chromosomes and DNA · 2009