Mutations at the Molecular Level Flashcards
What is an auxotroph?
A bacterium/ microorganism that can only be grown in specific conditions that have to be externally supplied. ie by a specific growth medium.
Explain how Beadle and Tatum’s results led to the one gene - one enzyme hypothesis?
They investigated three different mutants in bacteria, preventing them from growing on specific media. Found that the three mutations, though linked, were due to three different enzymes, producing three different enzymes. Leading to the one gene-one enzyme hypothesis.
What is the difference between genotype and phenotype?
The phenotype is the physical manifestation of a gene, the trait that the gene actually codes for. The genotype if the combination of alleles that determines the type of phenotypes that is expressed.
Why care about mutations?
Mutations cause genetic diversity, but more importantly, to us at least, give key insights into how genes and their products work.
What are mutations?
Mutations are heritable changes to the base sequence of a DNA molecule.
What did Beadle and Tatum do?
Designed an experiment where by looking at a specific group of mutations in bacteria, found that genes work by making enzymes, and created the one gene, one enzyme hypothesis.
What is the one gene one enzyme hypothesis and why is it significant?
That one gene is linked to one enzyme/ protein. Fundamentally is still correct today.
