Chargaff's ratios, 3D animation with narration
Erwin Chargaff found that in DNA, the ratios of adenine (A) to thymine (T) and guanine (G) to cytosine (C) are equal. This parity is obvious in the final DNA structure. (DNAi Location: Code > Finding the Structure > Pieces of the puzzle > Chargaff's ratios > Chargaff's ratios)
The DNA molecule is made up of very long chains of the 4 bases: A, C, G and T. In 1950, Erwin Chargaff published a paper stating that in DNA of any given species, the ratio of adenine to thymine is equal, as is the ratio of cytosine to guanine. This is known as Chargaff's ratios and it was a crucial clue that helped solve the structure of DNA. Chargaff's ratios are universal: all forms of life obey this rule. Only the balance of A-T pairs and C-G pairs varies between species.
erwin chargaff,chargaff dna,adenine guanine,dna molecule,dna structure,structure of dna,long chains,pieces of the puzzle,dna adenine,cytosine,thymine,base pairing,location code,narration,ratios,parity,pairs,clue,animation
- ID: 15495
- Source: DNALC.DNAi
- Download: MPEG 4 Video
15492. Discovering the double helix structure of DNA, James Watson, video with 3D animation and narration
James Watson used cardboard cutouts representing the shapes of the DNA bases to figure out how bases pair.
Erwin Chargaff talks about his discovery â a major step for building the DNA model.
James Watson talks about how he worked out the base pairing of DNA.
James Watson and Francis Crick explain how they solved the structure of DNA. Erwin Chargaff explain how he measured the levels of each of the four nitrogenous bases.
Deoxyribose and phosphate molecules form the uprights and nucleotide pair form the rungs of the DNA ladder.
Because it contains the directions for assembling the components of the cell, DNA is often thought of as the "instruction book" for assembling life.
Erwin Chargaff talks about his name for Chargaff's ratios.
Blocks to bases, DNA Has Four Units.
The DNA molecule is shaped like a twisted ladder.
Erwin Chargaff was the first to accurately measure nucleotide amounts in DNA.