Cytosine.
The nucleotide bases of DNA are located at the center of the twisted ladder or double helix structure. They are paired up across the helix, with adenine pairing with thymine and guanine pairing with cytosine through hydrogen bonds.
Adenine always pairs with thymine in DNA.
Thymine
Adenine is always paired with thymine in DNA and with uracil in RNA through hydrogen bonds.
The nucleotide bases you listed include thymine (T), cytosine (C), guanine (G), and adenine (A). If we consider pairs of bases in DNA, thymine pairs with adenine, and cytosine pairs with guanine. Thus, the other half of the sequence you provided, which consists of adenine and thymine, would be adenine (A) paired with thymine (T), and guanine (G) paired with cytosine (C).
In DNA, adenine always pairs with thymine.
This pairs up with Adenine just as Thymine had.
thymine
Imagine DNA as a ladder. The sugar and phosphate pattern are the vertical parts. Nucleobases are paired together and form the steps. A sugar, phosphate group and nucleobase form a nucleotide and each vertical column of the ladder runs in an opposite direction. One other feature is that a Purine must be paired with a Pyrimidine which is why A is always with T and C is always with G.
Thymine is always paired with adenine in a DNA molecule according to Chargaff's rules. They form a complementary base pair, with adenine pairing with thymine through two hydrogen bonds.
The nucleotide bases of DNA are located at the center of the twisted ladder or double helix structure. They are paired up across the helix, with adenine pairing with thymine and guanine pairing with cytosine through hydrogen bonds.
they are always paired together because when DNA is replicated they always find each other.
DNA polymerases will undo the work they have done if a previous nucleotide is not paired with a complementary base.
Adenine always pairs with thymine in DNA.
No, Uracil doesn't occur in double stranded DNA. Doublestranded DNA contains Guanine paired with Cytosine and Adenine paired with Thymine. In RNA, however, Adenine is always paired with Uracil instead of Thymine.
Thymine
Base pairing in DNA is very simple. It means that Adenine will always be paired with Thymine and Guanine will always be paired with Cytosine.