Guanine, pairing with cytosine deoxyribonucleic acid

DNA stands for deoxyribonucleic acid. It is the biological blueprint of life. DNA is made up of a double-stranded structure consisting of sugar (deoxyribose) and phosphate back bone, cross linked with two types of nucleic acids referred to as purines (adenine and guanine) and pyrimidines (thymine and cytosine) (Fig. 1). The cross linking nucleic acids always pair a purine with a pyrimidine, such that adenine always pairs with thymine and guanine always pairs with cytosine. 

Fig. N-9. The spiral structure of deoxyribonucleic acid, or DNA— the basic building block of life on earth. It s a double helix (a double spiral structure), with the sugar (deoxyribose)-phosphate (phosphoric acid) backbone represented by the two spiral ribbons. Connecting the backbone are four nitrogenous bases (a base is the nonacid part of a salt) adenine (A) paired with thymine (T), and guanine (G) paired with cytosine (Q with the parallel spiral ribbons held together by hydrogen bonding between these base pairs. Adenine and guanine are purines, while thymine and cytosine are pyrimidines.

In nature, the life is encoded by deoxyribonucleic acid (DNA), which encompasses all the information for self-replication, development, and survival of the organism. Indeed, DNA is a polymer having many repetitive units comprised of a sugar molecule, a heterocyclic base, and a phosphate group that links the units together. Noticeably, the heterocyclic bases found in DNA include adenine (A), guanine (G), cytosine (C), and thymine (T), which can pair highly selectively to each other via specific interactiOTis with A G and C T (Champe and Harvey 1994). 

DNA Deoxyribonucleic acid the genetic material of cells, containing nucleotides with deoxyribose sugar, phosphate, and the four bases adenine, thymine, guanine, and cytosine, double helix The hehcal shape of the donhle chain of DNA that is like a spiral staircase with a sugar-phosphate hackhone on the outside and base pairs like stair steps on the inside, frameshift mutation A mutation that inserts or deletes a hase in a DNA sequence. 

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