Table of Contents
- 1 How do amino acid sequences support the theory of evolution?
- 2 How does comparing proteins support the theory of evolution?
- 3 Why would the scientist compare the amino acid sequences of proteins common to those similar species?
- 4 How do amino acid sequence similarities show how closely related organisms are to one another?
- 5 Do you agree that the more differences in amino acid sequence the more closely related organisms are?
- 6 How can a comparison of proteins help scientists identify a common ancestor between two species?
- 7 How are amino acid sequences used to figure out if two species are closely related?
How do amino acid sequences support the theory of evolution?
That two species and their common ancestor have similar DNA is strong evidence supporting evolution. Protein amino acid sequences can also be used to compare similarities between species. Proteins are made from amino acids and the sequence of these amino acids is controlled by genes.
How does comparing proteins support the theory of evolution?
Proteins govern the traits chosen (or not) in natural selection. For all organisms, a single Genetic Code translates the sequence of nucleotides in a gene into a corresponding chain of 20 amino acids. By itself, the universality of DNA genes and their code for proteins is strong evidence for common ancestry.
How can the study of comparing genetic sequences provide evidence for evolution?
Molecular similarities provide evidence for the shared ancestry of life. DNA sequence comparisons can show how different species are related. Fossils provide evidence of long-term evolutionary changes, documenting the past existence of species that are now extinct.
Why would the scientist compare the amino acid sequences of proteins common to those similar species?
Why would the scientist compare the amino acid sequences of proteins common to those similar species? Amino acid sequence differences provide evidence of gene flow among the species. Amino acid sequence differences reflect the accumulated differences in the DNA of the species.
Because the DNA sequence determines a protein’s amino acid sequence, a gene shared by two closely related organisms should have similar, or even identical, amino acid sequences. That’s because closely related species most likely diverged from one another fairly recently in the evolutionary span.
Why can comparing amino acid data lead to the same conclusions as comparing DNA data?
Comparing the DNA or amino acid sequences in different species can show how closely related species are in evolutionary terms. The more similar the sequence, the more closely related the species.
Biologists believe that the greater the similarity between the amino acid sequences of two organisms, the closer their relationship. Conversely, the greater the differences, the more distant the relationship. You will also study amino acid differences and infer evolutionary relationships among some diverse organisms.
How can a comparison of proteins help scientists identify a common ancestor between two species?
By comparing the type and sequence of amino acids in similar proteins from different species, the degree of similarity can be established. The degree of difference between proteins enables an estimate of the amount of evolution that has taken place since two species developed from a common ancestor.
What do similarities and differences in anatomical structures and embryological development tell us about the relationships between organisms?
Some organisms have anatomical structures that are very similar in embryological development and form, but very different in function. By comparing the anatomy of these organisms, scientists have determined that they share a common evolutionary ancestor and in an evolutionary sense, they are relatively closely related.