(ii) Biochemical Evidence: Protein/Amino Acid Sequences Flashcards
How can comparative biochemistry be used for protein and amino acid sequences?
It can be used to compare the sequence of amino acids in proteins in different species
What are proteins made of?
long chains of amino acids
What can the degree of difference between proteins determine?
How much time has passed since two species developed from a common ancestor.
The greater no. of amino acids that are different means
The longer the period of time
What are ubiquitous proteins?
present in all species
carry out same functions
What is Cytochrome C?
ubiquitous protein
performs essential step in production of cellular energy
The arrangement of amino acids in Cytochrome C is similar in different species. What does this suggest?
the proteins have descended from an ancestral Cytochrome C molecule found in a primitive microbe.
Is the similarity in the arrangement of amino acids only for Cytochrome C? Give an example.
No, other ubiquitous proteins show similar results.
e.g. alpha and beta chains of haemoglobin
identical in humans & chimpanzees
gorillas- differs by 1
gibbons- differs by 3
