The two threads are held together by bonds between base pairs. There are four types of base - adenine, thymine, cytosine and guanine. All human cells contain DNA. The 3 billion pairs of bases in ...

Comparison of a single-stranded RNA and a double-stranded DNA with their corresponding nucleobases. (Image: Wikimedia Commons, CC SA 3.0) The most common type of base pairing is the Watson-Crick base ...

DNA is a complex molecule that consists of two strands coiled around each other to form ... These mechanisms can detect and correct different types of DNA damage, such as base mismatches, ...

and several nitrogen-containing bases. Later it was found that the sugar in nucleic acid can be ribose or deoxyribose, giving two forms: RNA and DNA. In 1943, American Oswald Avery proved that DNA ...

Insertions and deletions are two other types of mutations that ... excess flexibility of the DNA strand and the subsequent mispairing of bases is another. Environmental exposure to certain ...

Then, a protein known as helicase attaches to and breaks apart the hydrogen bonds between the bases on the DNA strands, thereby pulling apart the two strands. As the helicase moves along the DNA ...

Nitrogen atoms in DNA are bonded with either three or two atoms, resulting in different ... depending on the base and nitrogen type. These orientations vary across the four bases: adenine, guanine ...

DNA molecules ... have the same two alleles or two different ones. The sequence of every amino acid in a protein is determined by the triplet code, which is a code of three bases.