Question

Given below are two statements:
I. Cytosine and guanine are formed in equal quantities in DNA hydrolysis. 
II. Adenine and uracil are formed in equal quantities in RNA hydrolysis. The correct answer is:

• A. Statements I, II both are correct
• B. Statements I, II both are incorrect
• C. Statement I is correct but statement II is incorrect
• D. Statement I is incorrect but statement II is correct

Hint:

In DNA, cytosine and guanine are always found in equal quantities due to complementary base pairing, but this does not apply to adenine and uracil in RNA.

Answer 1

The Correct Option is C

Step 1: Understanding DNA Base Pairing 
- DNA follows Chargaff’s rule, which states that the number of cytosine (C) equals the number of guanine (G), and the number of adenine (A) equals the number of thymine (T).
- Hence, in DNA hydrolysis, cytosine and guanine are produced in equal quantities.
Step 2: RNA Hydrolysis and Base Pairing 
- RNA consists of adenine (A), uracil (U), cytosine (C), and guanine (G). 
- Unlike DNA, RNA does not follow Chargaff’s rule because it is single-stranded. 
- Adenine and uracil are not necessarily in equal amounts in RNA hydrolysis. 
Thus, statement I is correct, but statement II is incorrect.

Answer 2

Given below are two statements:

I. Cytosine and guanine are formed in equal quantities in DNA hydrolysis.
II. Adenine and uracil are formed in equal quantities in RNA hydrolysis.

Analysis:
Statement I:
In double-stranded DNA, cytosine pairs with guanine through three hydrogen bonds. Because of base pairing rules (Chargaff's rule), the number of cytosine (C) bases always equals the number of guanine (G) bases. Hence, during hydrolysis of DNA, cytosine and guanine are released in equal quantities.
So, Statement I is correct.

Statement II:
In RNA, adenine pairs with uracil during base pairing, but RNA is typically single-stranded. There is no strict base pairing rule that ensures equal quantities of adenine and uracil. Therefore, adenine and uracil are not necessarily present in equal amounts in RNA hydrolysis.
So, Statement II is incorrect.

Conclusion:
The correct answer is:
Statement I is correct but Statement II is incorrect.