During the Lederberg and Tatum experiment, theresearchers compared the growth of mutant strains under twoscenarios: mixed strains or unmixed strains. When the unmixedstrains were plated on the experimental growth medium, whywere no colonies observed to grow? When the mixed strainswere plated on the experimental growth medium, 10 colonieswere observed. What was the significance of these colonies?

17 A nutrient agar plate labeled 10-5 mL produced 154 colonies after incubation. a. What was the cell density in the original sample? ET b. What combination(s) of volumes and dilution factors could have been used to inoculate this plate? A nutrient agar plate labeled 10-7 mL produced 62 colonies after incubation. a. What was the cell density in the original sample? b. What combination(s) of volumes and dilution factors could have been used to inoculate this plate? The original cell density in a sample is 2.79 x 100 CFU/mL. Which sample volume should yielda countable mL.) plate? (Express your answer as 10 20 The original cell density in a sample is 5.1 x 10° CFU/mL. Which sample volume should yield a countable plate? (Express your answer as 10 mL.) 21 A sample has a density of 1.37 x 105 CFU/mL. a. What sample volume should yield a countable plate? b. Which two dilution tubes could be used to produce this sample volume? How? 22 A sample has a density of 7.9 x 10° CFUlmL. a. What sample…

What was the purpose for doing the colony PCR?

Based on the quantitation data, please indicate how you would dilute the following samples. Fill in each blank with the appropriate information. Item 1: DNA concentration - 22.6 ng/uL Dilution factor - 1: Add uL DNA extract to uL buffer Final dilution concentration = ng/ul Item 4: DNA concentration - 3.75 ng/uL Dilution factor - 1: Add uL DNA extract to uL buffer Final dilution concentration = ng/ul

Thirty corn seedlings of equal size were randomly assigned to one of three treatment groups. At the beginning of the experiment, the plants in group I were dried and the mass was determined. The plants in group Il were maintained in light for a week. The plants in group III were maintained in the dark for a week. All conditions, other than light, were the same for groups IlI and III. At the end of the week, the plants in groups Il and III were dried and the mass was determined. The experimental results are provided in the table. Initial Dry Mass of 10 Plants (g) Dry Mass of 10 Plants After One Week (g) Change in Dry Mass of 10 Plants Over One Week (g) Treatment Group Treatment Nohe 14.8 II Light 32.8 +18 III Dark 11.7 -3.1 (a) To explain the increase in mass of the light-grown plants, identify ONE inorganic source of new plant mass and connect it to the cellular process underlying the increase in mass. (b) To explain the decrease in mass of the dark-grown plants, identify the overall…

"Hybridization of a single-stranded DNA molecule attached to a fluorophore with a preparation of metaphase chromosomes that have been partially denatured" is a description of which laboratory method?