Question

according to chargaffs rule, base pairing in dna should resemble which of the following?

\\(a = t; c = g\\)
\\(a = c; t = g\\)
\\(a = g; t = u\\)
\\(a = u; c = g\\)

Explanation:

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<reasoning>

Identify the core principle of Chargaff's rules

Chargaff's rules state that in DNA, the amount of adenine (A) equals thymine (T), and the amount of cytosine (C) equals guanine (G).

Match the rules to base pairing

This 1:1 ratio reflects the specific complementary base pairing where adenine pairs with thymine, and cytosine pairs with guanine.

Evaluate the given options

• \(A = T; C = G\): Correctly represents Chargaff's rules.
• \(A = C; T = G\): Incorrect pairing.
• \(A = G; T = U\): Incorrect pairing, and uracil (U) is found in RNA, not DNA.
• \(A = U; C = G\): Uracil (U) is not a standard base in DNA.

</reasoning>

<answer>
<mcq-correct>(A) A = T; C = G</mcq-correct>
<mcq-option>(B) A = C; T = G</mcq-option>
<mcq-option>(C) A = G; T = U</mcq-option>
<mcq-option>(D) A = U; C = G</mcq-option>
</answer>

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Answer:

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<reasoning>

Identify the core principle of Chargaff's rules

Chargaff's rules state that in DNA, the amount of adenine (A) equals thymine (T), and the amount of cytosine (C) equals guanine (G).

Match the rules to base pairing

This 1:1 ratio reflects the specific complementary base pairing where adenine pairs with thymine, and cytosine pairs with guanine.

Evaluate the given options

• \(A = T; C = G\): Correctly represents Chargaff's rules.
• \(A = C; T = G\): Incorrect pairing.
• \(A = G; T = U\): Incorrect pairing, and uracil (U) is found in RNA, not DNA.
• \(A = U; C = G\): Uracil (U) is not a standard base in DNA.

</reasoning>

<answer>
<mcq-correct>(A) A = T; C = G</mcq-correct>
<mcq-option>(B) A = C; T = G</mcq-option>
<mcq-option>(C) A = G; T = U</mcq-option>
<mcq-option>(D) A = U; C = G</mcq-option>
</answer>

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