Genetics Answers

Which of the following enzyme can act as a polymerase as well as exonuclease?

a. RNA polymerase I c. DNA polymerase I

b. RNA polymerase III d. DNA polymerase III

Identify the F1 generation from a colourblind father and a mother who is homozygous for colour vision.

How does replica plating demonstrate that muta- tions to antibiotic resistance can arise even in cells that have never been exposed to the antibiotic?

What is the purpose of the liver extract in the Ames test for chemical mutagens?

What is “mismatched” in the process of mismatch repair?

What is “loss of heterozygosity,” and how is this phenomenon related to the progression of some types of cancer?

What is apoptosis, and what role does it play in preserving the integrity of the genome of a multi- cellular organism?

What is a cell-cycle checkpoint? Which check- points are emphasized in this chapter, and what does each “check” for?

What would happen if an electrolyte solution was not used to make the gel for gel electrophoresis?

The following fragments were obtained after digestion of a sequence using restriction enzymes: 5.3 kb, 2.1 kb, 6.8 kb, 3.6 kb, 1.1 kb, 2.2 kb. Order the fragments, moving from the fastest migration to the slowest migration on a gel. Which two fragments may be difficult to isolate on a gel? Why? Sketch the resulting gel after running the fragments on it. Assume that the fragments were all run in one lane. Label the positions of the positive and negative electrodes.