Genetics Answers

Recombinase is a protein that finds adjacent pieces of DNA that have nearly identical DNA sequences, facilitates a backbone break in each piece of DNA near the identical sequence, physically rearranges the pieces of DNA, and then facilitates backbone repair. How does recombinase know when it’s found the right combination of DNA?

Huntington’s disease is caused by an allele at the IT15 gene. The allele produces RNA leading to
a protein that has a novel impact on how it interacts with other proteins, causing
neurodegenerative action. Is this allele best classified as functional, non-functional, or
abberant? Justify your answer in 1-2 sentences.

Unlike eukaryotic cells, prokaryotic cells do not have to remove introns and splice together exons to make a functional mRNA molecule.

Which type of cell has an obvious advantage in terms of energy cost to synthesize proteins? Which type of cell has a greater opportunity to control gene expression? Explain.

What is the advantage of altering the protein that is made, instead of just stopping protein production?

Why is it important for gene regulation to be reversible in a cell?

If a wildtype bacterium is grown in the presence of the sugar X-gal, transcription of the polycistronic m-RNA does not occur. What is X-gal unable to do? Without adding lactose (or genetically modifying the bacteria), how could you fix this problem

If a lacI - bacterium is grown in the presence of the sugar X-gal, a blue dye appears; however, the concentration of X-gal decreases over time. What has happened to the X-gal?

In a random mating population of 20000, 16800 individuals are the dominant then how many individuals will be homozygous?

Rough-coated guinea pigs crossed with smooth-coated ones produce only rough-coated offspring. What results would be expected from breeding here offspring with each other?

Detail the various cell types of Immune System and their roles