Deoxyribose acid (DNA)
Ribonucleic Acid (RNA)
DNA is stored in the nucleus, RNA is found in the cytoplasm
Nucleic Acids are long chain molecules and their building blocks are called nucleotides, more complicated than the acids
Nucleotides are compromised of a pentose sugar, a phosphate, and an organic base.
The Sugar is two possibilities: ribose gives RNA and deoxyribose gives DNA
The Phosphate H3PO4 (P forms 5 bonds with other atoms)
The Organic Base: the nitrogenous base
Five Bases in DNA:
A, C, T and G are found in DNA.
A, C, U and G are found in RNA.
Adenine, Thymine and Uracil are capable of forming two hydrogen bonds while Cytosine and Guanine can form three.
Adenine and Guanine are purines
Cytosine, Thymine, and Uracil are pyrimidines
phosphate + sugar + organic base ---> nucleotide + 2 water
Nucleotides can be connected together by a condensation reaction between the phosphate of one nucleotide and the sugar of another.
Covalent bonds are formed between the phosphate and sugar and a single strand is made with a backbone of phosphate and (deoxy)ribose and an organic base attached to every ribose.
The structure of DNA is a double helix
The back one is made of alternating phosphate - sugar groups. The rungs of the twisted ladder which DNA resembles are the organic base pairs.
Pairing for DNA makes A and T or C and G
Pairing for RNA makes A and U, C and G.
The DNA double helix has to unwind and the two strands need to seperate
Free nucleotides which are floating around in the nucleus for complementary pairs with the nucleotides of both of the DNA strands.
The enzyme DNA polymerase is responsible for when the nucleotides which have formed complementary base pairs with the nucleotides on the old strand now join to each other
Because the organic base will only fit with one other one complementary base pairing,...