There are 10 E. coli cells in a test tube.  After 4 generations in exponential phase, how many E. coli are there?

Fifteen bacterial colonies growing on a complete medium (that means that they have all of nutrients that they need supplied in the dish, and they don't actually need to synthesize these compounds to survive) are transferred to minimal medium. Twelve of the colonies grow on minimal medium. Three colonies do not grow on minimal medium. But, if these three colonies are put on a plate that has minimal medium supplemented with the amino acid serine (min + Ser), they all What does this suggest about the three bacterial colonies (pick all that apply)? grow. They lack the ability to synthesize their own serine. O They are probably wild-type. They probably have a mutation that causes them to lack a certain protein. They probably have a mutation that causes them to be unable to perform translation. O They probably have a mutation that causes them to be unable to perform transcription. O They are able to synthesize everything that they need to grow except for serine.

Consider the five E. coli merodiploid strains listed here. Strain #1 I+P+O+Z-Y+/I+P+OcZ+Y+ Strain #2 I+P+O+Z+Y+/I-P+OcZ+Y- Strain #3 I+P+O+Z-Y+/I-P+OcZ+Y- Strain #4 I-P-O+Z+Y-/I+P+OcZ-Y+ Strain #5: ISP+O+Z+Y+/I-P+O+Z+Y- Which of these strains will be inducible for expression of b-galactosidase? Select all correct answers. A.) Strain #2 B.) Strain #3 C.) Strain #1 D.) Strain #4 E.) None of these F. )Strain #5

You have several different media onto which you inoculated eight strains of yeast (A-H). The media include a rich medium, an unsupplemented minimal medium, and minimal media each supplemented with one vitamin. Of the yeast strains, one is a prototroph and seven are auxotrophs for a vitamin. After overnight incubation, the following results were observed (tan patches represent growth): D plate 1 (A) B DE F GH plate 5 plate 4 plate 6 Which plate contains an unsupplemented minimal medium? [Select] Which plate contains a rich medium? [Select] plate 2 Which strain is a prototroph? [Select] Strain E is an auxotroph for niacin. Which plate reveals this specific auxotrophy? [ Select] plate 3 plate 7 One strain is an auxotroph for both choline and pantothenic acid. Which one is this most likely to be? [Select]

For the state science fair, a student investigated the change in a yeast population over five days. The experimental design included the following. • The yeast were grown on a (5%)glucose (sugar) media in a closed, sterile petri dish for five days. • The petri dish was kept at a constant warm temperature (30°C) in an incubator. • The petri dish was observed under a microscope each day during the study, and the number of live cells in the same area of the petri dish was recorded. • Illustrations of observations were made each day of the investigation. Illustrations of Daily Observations of Growing Yeast Colonies :- Day 1 Day 2 Day 3 Day 4 Day 5 18 Cells 58 Cells 111 Cells 69 Cells 35 Cells

If Microbe A and Microbe B have whole genome similarity of 68%, as determined by DNA-DNA hybridization, they should be considered the same species.

If you counted 300 colonies on a plate that had a 10-5 dilution of bacteria culture, how many colonies might you expect on a plate that had a 10-6 dilution of the same bacterial culture?

A slant is inoculated with 100 E.coli cells. The slant is left at room temperature where the generation time is 1 hour. How many E. coli are on the slant in 6 hours? If the slant was initially put in the 37C incubator, with a 20 minute generation time, how many more cells would have grown in the same time period?

You infect bacteria with two phages during a cis test. This produces a lysate that contains phage particles. Before you can count outcomes, you need to work out the amount of phage to use in subsequent experiments. You start by making two ten- fold serial dilutions of the lysate and then add 1mL of the final diluted lysate to a plate of permissive strain e.coli. You observe 10 plaques. How many phage per mL were present in the original lysate? a. 10 phage/mL o b. 3,300 phage/mL c. 10,000 phage/mL o d. 1,000 phage/mL e. 33 phage/mL

During the process of conjugation between two bacteria, each bacterium transfers some of its DNA into the other bacterium.    True False