Define the term genetic complementation.

Locate another example of genetic complementation in this book and describe how genetic complementation works in that case.

Penicillin was first used in the 1940s to treat gonorrhea infections produced by the bacterium Neisseria gonorrhoeae. In 1984, according to the CDC, fewer than 1% of gonorrhea infections were caused by penicillin-resistant N. gonorrhoeae. By 1990, more than 10% of cases were penicillin-resistant, and a few years later the level of resistance was at greater than 95%. Almost every year the CDC issues new treatment guidelines for gonorrhea that identify the recommended antibiotic drugs and dosages.

What are the short-term implications of these frequent changes for physicians and clinics that treat sexually transmitted diseases like gonorrhea and for individuals infected with gonorrhea?

Penicillin was first used in the 1940s to treat gonorrhea infections produced by the bacterium Neisseria gonorrhoeae. In 1984, according to the CDC, fewer than 1% of gonorrhea infections were caused by penicillin-resistant N. gonorrhoeae. By 1990, more than 10% of cases were penicillin-resistant, and a few years later the level of resistance was at greater than 95%. Almost every year the CDC issues new treatment guidelines for gonorrhea that identify the recommended antibiotic drugs and dosages.

Why is the CDC so active in making these recommendations?

A wild-type culture of haploid yeast is exposed to ethyl methanesulfonate (EMS). Yeast cells are plated on a complete medium, and 6 colonies (colonies numbered 1 to 6) are transferred to a new complete medium plate for further study. Four replica plates are made from the complete medium plate to plates containing minimal medium or minimal medium plus one amino acid4 (replica plates numbered 1 to 4) with the following results:

Identify the colonies that are auxotrophic (mutant). What growth information leads to your answer? 

A wild-type culture of haploid yeast is exposed to ethyl methanesulfonate (EMS). Yeast cells are plated on a complete medium, and 6 colonies (colonies numbered 1 to 6) are transferred to a new complete medium plate for further study. Four replica plates are made from the complete medium plate to plates containing minimal medium or minimal medium plus one amino acid4 (replica plates numbered 1 to 4) with the following results:

Identify the colonies that are prototrophic (wild type). What growth information leads to your answer?