BIOL 1201 Chapter : Molecule Of Heredity
Document Summary
Dna: molecule of heredity: bacteria, archae, ukarea. Atgc - all living things have nucleotides. 23 pairs of chromosomes = 46 total chromosomes. 4 nucleotides of dna: thymine, cytosine, adenine, guanine recognize the basic structure of each nucleotide. A&t are weaker because they only have 2 hydrogen bonds. G&c are stronger because they have 3 hydrogen bonds. Chargaff"s rule- a is always equal to t; g is always equal to c x-ray diffraction of dna. Maurice wilkins and rosalind franklin knew dna formed a helix by the patterns seen in x-ray diffraction. Order of nucleotides in a dna molecule can encode large amount of information. Dna 10 nucleotides long has 4^10 different possible combinations (1,048,576 combinations) Keeps half of original information and makes half of a new strand. Usually occurs with little error or change(mutation free) All 23 pairs must be replicated during synthesis process. Protein catalyzes reaction(unzips dna) breaks hydrogen bonds.