Comparative Biochemistry1) When comparing DNA & protein structure there exists auniversal (across all species) genetic code for reproduction.DNA is made-up of 4 universal nucleotides, commonlyreferred to as A, T, C, G.
Comparative Biochemistry1) Proteins are made-up from 20 universal aminoacids.
Comparative BiochemistryThe order of amino acids in a protein aredetermined by the order of nucleotides in DNA.(If there is a mutation in the DNA, the protein willlikely also change) *Muscular dystrophy is a genetic disease caused by mutation. It is characterized by muscle weakness and loss of muscle tissue. Left: A healthy male. Right: A male with muscular dystrophy.
Comparative BiochemistryA point mutation is the altering of a DNA strandwith a single nucleotide. There are 3 kinds:i) Insertion – A nucleotide is added and all othersare moved forward.Ex.Initial: ATA CGC AGABecomes: ATA CGT CAG A
Comparative Biochemistryii) Deletion – A nucleotide is removed and allothers are moved backward.Ex.Initial: ATA CGC AGABecomes: ATA CGA GA
Comparative Biochemistryiii) Substitution – A nucleotide is switched withanother nucleotide.Ex.Initial: ATA CGC AGABecomes: ATA CGT AGA
Comparative Biochemistry2) Comparing common genes: A gene is a DNA sequence that is used to make aprotein. By comparing gene or amino acid sequences, wecan see how closely related 2 species are. cow CTATG GTTCC TAAGC ACAAG deer CTATG GTTCC TAAGC ACGAA whale CTATC CTTCC TAAGC ATAAA hippo CTATC CTTCC TAAGC ATAAA pig CCATT GTTCC CAAGC GTAAA rat CCATC TTTCC TAAGC TCAAA
Comparative Biochemistry Example: the protein hemoglobin (for gas exchange). This chart compares short amino acid chains ofdifferent animals.
Comparative Biochemistry Example: the protein cytochrome c (for respiration)contains between 100 and 104 amino acids. This chart shows how many differences existbetween 2 species.
How is Comparative Biochemistry Evidence of Evolution?