complementary base

American  

noun

Genetics.

1. either of the nucleotide bases linked by a hydrogen bond on opposite strands of DNA or double-stranded RNA: guanine is the complementary base of cytosine, and adenine is the complementary base of thymine in DNA and of uracil in RNA.

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Usage

What is a complementary base? A complementary base is either of the two nitrogen-containing sections of a nucleotide that bond together to connect strands of DNA or RNA. DNA and RNA are complex molecules that are central to genetics and both are made of things called nucleotides. Nucleotides are made of a sugar molecule, phosphoric acid, and a base. In chemistry, the word base refers to a chemical that will give or receive electrons or protons, and the two partner bases that share with each other in the nucleotides of DNA and RNA are called complementary bases. The arrangement of the complementary bases is crucial to DNA’s structure and is what gives it its characteristic double helix shape.

Example Sentences

DNA is a double helical structure in which complementary base pairing occurs.

From Textbooks • Jun. 9, 2022

One or more of these molecules interacts by complementary base pairing with some of the nucleotides in the pre-mRNA transcript.

From Textbooks • Jun. 9, 2022

Base pairing takes place between a purine and pyrimidine; namely, A pairs with T and G pairs with C. Adenine and thymine are complementary base pairs, and cytosine and guanine are also complementary base pairs.

From Textbooks • Jun. 9, 2022

Describe the structure and complementary base pairing of DNA.

From Textbooks • Jun. 9, 2022

The overhangs are called “sticky ends” because they can bond, or “stick,” to a DNA fragment with the complementary base sequence.

From Textbooks • Jan. 1, 2018