In DNA the nitrogen bases are either purines or pyrimidines.
Adenine (A) and guanine (G) are purines, and thymine (T) and cytosine (C) are pyrimidines.
A pairs with T on the complementary strand, and G with C.
In RNA, A pairs with U (uracil). U is specific for RNA, and T is found only in DNA.
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If you have the same crossword puzzle homework as I do, the specific answer is:
BASE PAIRS
The nitrogen bases of DNA pair up according to specific base-pairing rules: adenine (A) pairs with thymine (T) and guanine (G) pairs with cytosine (C). This base pairing forms the rungs of the DNA ladder structure, with hydrogen bonds holding the pairs together.
There are 3 unpaired electrons in an isolated nitrogen atom, the nitrogen molecule has none.
Each step of the DNA ladder is made up of two nitrogen bases that form a base pair - adenine with thymine and guanine with cytosine.
You must be aware that there are four nitrogen bases - adenine (A), thyamine (T), guanine (G) and cytosine (C) [unlike DNA in an RNA molecule uracil (U) is present instead of cytosine (C)]. Each nitrogen base together with a five carbon sugar molecule (ribose in case of RNA and deoxyribose in case of DNA) and a phosphate group forms a nucleotide [not to be confused with nucleoside - just sugar and base, no phosphate group]. Adenine base pairs with thymine with the formation of two hydrogen bonds and guanine with cytosine using three hydrogen bonds. A base pair consists of two nucleotides paired using the above mentioned hydrogen bonds.
The four nitrogen bases of DNA (adenine, guanine, cytosine, thymine) are found in the double helix structure of DNA, where they pair up to form the rungs of the ladder-like structure. They are held together by hydrogen bonds in specific base pair combinations (A-T and C-G).
Base Pair
It means which nitrogen base pairs with the other Nitrogen bases: A-t T-a C-g G-c
When a nitrogen bases floating in the nucleus ipair up with the basis on each half of the DNA molecule. Remember that the pairing of bases follows definite rules: A always pairs with T, while G always pairs with C. Once the two new bases are attached, two new DNA are formed. Information found: by a 9th grade science text book Name of book: unknown
The order of the bases in each new DNA molecule exactly matches the order in the original DNA molecule by bringing them together with the original DNA cells.
The nitrogen bases are held together by hydrogen bonds.
Base pair
The two chains are connected by hydrogen bonding between nitrogen bases to form a long double-stranded molecule.So hydrogen bonding determines which nitrogen bases form pairs of DNA.
The category of nitrogen bases that consists of two rings is the purines.A nitrogenous base is an organic compound that owes its property as a base to the lone pair of electrons of a nitrogen atom. Notable nitrogenous bases include purines.Purines have two fused rings of carbon and nitrogen atoms.
Base pairing refers to the pairing of complimentary nitrogen bases, either during DNA replication, or transcription and translation. In DNA, the bases adenine and thymine pair together, and guanine and cytosine pair together. In RNA, the base uracil takes the place of the base thymine. The bases that pair together are said to be complimentary to each other.
A Nitrogenous (nitrogen-containing) base is a nitrogen-containing molecule having the chemical properties of a base.It is an organic compound that owes its property as abase to the lone pair of electrons of a nitrogen atom.
The middle of a DNA molecule consists of nitrogenous bases (adenine, thymine, cytosine, and guanine) that pair up to form the genetic code. These bases are connected by hydrogen bonds, forming the double helix structure of DNA.
Uracil would base pair with adenine on a RNA molecule.