Find the thy mutant in the first place

Reference no: EM1397564

A biologist was testing E. coli for thymidine requirement. She found a thy- point mutant and wanted to study reversion to thy+. She grew 20 cultures of the thy- mutant strain and plated them onto 20 plates that contained media to select for thy+ revertants. She obtained a total of 460 colonies. Six of the plates showed no colonies.
a) If 5 x 108 cells were spread on each plate what was the reversion frequency and the reversion rate? b) Explain what steps she could have taken to find the thy- mutant in the first place, and why she did each step.
c) She also wanted to study the type of mutation that occurred during formation of the original thy- cells. The mutagens HA (a base modifyer), BU (a base analogue), and acridine (an intercalator) were each added to thy- cells. Only BU reverted the thy- mutants to WT. Briefly describe the types of mutations each mutagen causes. Based on this information what was the original mutation to thy- to begin with? Explain your reasoning.

Reference no: EM1397564

Questions Cloud

Compute the volume of water vapour : Compute the volume of CO 2 and water vapour produced and the volume of oxygen remaining, when 20.0 dm 3 of propane reacts with 120.0 dm 3 of oxygen. All gas volumes are measured at the same temperature and pressure.

Question about classical genetics : A bacterial gene is known to spontaneously mutate at a high frequency. A study of one mutant gene product shows that the mutant protein made is shorter than the wildtype protein by four amino acids.

Concepts involved in hypothesis testing : Explain the concepts involved in hypothesis testing, including what hypothesis testing is, and an explanation of the four types of scales used to measure data.

Independant simple random samples : Assuming the percentages are based on independant simple random samples of 1,000 first year college students drawn each year.

Find the thy mutant in the first place : A biologist was testing E. coli for thymidine requirement. She found a thy- point mutant and wanted to study reversion to thy+. She grew 20 cultures of the thy- mutant strain.

Benson trusts the best way to truly escape from his humdrum : Benson trusts the best way to truly escape from his humdrum life is on a sport-style motorcycle. He has nearly saved enough money to buy himself one

Comparing sample means : Why are you no longer directly comparing sample means? How does using the F test - the analysis of variance (ANOVA) reduce your Type I error rate? What is the difference between a within-groups and a between-groups variance?

How many oxygen molecules are required : What is the theoretical yield of SO 3 produced by the quantities described in Part A and How many Oxygen molecules are required to react with 7.82g of S?

How were the ideas significant to the success of the product : How did 3M's David Windorski get thoughts from college students to help him in designing the final commercial version of the Post-it Flag Highlighter?

User Account

All Pages