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Plant Molecular biology. Lap.1. Plant Molecular biology. Central dogma. Structure of DNA. Components of DNA DNA has two strands A phosphate- deoxyribose polymer composes the backbone of the DNA adjacent sugars are connected by phosphodiester bonds
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Plant Molecular biology Lap.1
Structure of DNA Components of DNA • DNA has two strands • A phosphate-deoxyribose polymer composes the backbone of the DNA • adjacent sugars are connected by phosphodiester bonds • nitrogenous bases are convalently bonded to the 1' carbon of the deoxyribose • the two DNA strands are antiparallel • the two strands are held together by hydrogen bonds between complementary bases • adenine hydrogen bonds (base pairs) to thymine • guanine hydrogen bonds to cytosine
When DNA replicates two idential DNA double helices are formed.
Structure of RNA : • The basic components of RNA are the same than for DNA with two major differences. • The pyrimidyne base uracil replace thymine • ribose replace deoxyribose. • Adenine and Uracil for a base pair formed by two hydrogen bonds. • Most cellular RNA molecules are single stranded. • The major role of RNA is to participate in protein synthesis,