AP Biology DNA and RNA Structure

Cytosine bonds with

• guanine through a covalent bond

• guanine through a hydrogen bond

• cytosine through a hydrogen bound

• guanine through an ionic bond

guanine bonds with

• cytosine through a covalent bond

• cytosine through a hydrogen bond

• guanine through a hydrogen bound

• thymine through an hydrogen bond

adenine bonds with

• uracil through a covalent bond

• thymine through a hydrogen bond

• cytosine through a hydrogen bound

• thymine through an ionic bond

thymine bonds with

• uracil through a covalent bond

• adenine through a hydrogen bond

• cytosine through a hydrogen bound

• adenine through an ionic bond

Purines consist of

• A, G

• C, U, T

• G, A, U

• T, C

Pyrimidines consist of

• C, U, T

• A, G

• A, G, U

• G, C

Double ring structure

• purines

• pyrimidines

single ring structure

• purines

• pyrimidines

Adenine to Thymine has

• 2 hydrogen bonds

• 3 hydrogen bonds

• 1 hydrogen bond

• 4 hydrogen bonds

Cytosine to Guanine has

• 2 hydrogen bonds

• 3 hydrogen bonds

• 1 hydrogen bond

• 4 hydrogen bonds