AP BIOLOGY

Detailed explanation-1: -The two strands are held together by hydrogen bonds between pairs of bases: adenine pairs with thymine, and cytosine pairs with guanine.

Detailed explanation-2: -In DNA, adenine always pairs with thymine (A-T), and guanine always pairs with cytosine (G-C).

Detailed explanation-3: -Whereas, guanine and cytosine are complementary to each other and pair via three hydrogen bonds.

Detailed explanation-4: -Adenine always binds to thymine, while cytosine and guanine always bind to one another. This relationship is called complementary base paring. These complementary bases are bonded together via hydrogen bonds, which can be easily broken apart when the DNA needs to unzip and duplicate itself.

Detailed explanation-5: -Cytosine (C) is one of the four nucleotide bases in DNA, with the other three being adenine (A), guanine (G) and thymine (T). Within a double-stranded DNA molecule, cytosine bases on one strand pair with guanine bases on the opposite strand. The sequence of the four nucleotide bases encodes DNA’s information.