Chemistry 1) Take 1 mL of a liquid bacterial culture (aka original culture) and mix it with 9 mL of uninoculated liquid medium in tube A. Take 0.1 mL from tube A and mix it with 9.9 mL of uninoculated medium in tube B. Take 0.2 mL from tube B and mix it with 99.8 mL of uninoculated medium in tube C. Take 0.05 mL from tube C and mix it with 19.95 mL of uninoculated medium in tube D. Take 0.25 mL from tube D and mix it with 99.75 mL of uninoculated medium in tube E. - If the original culture density were 3 x 107 cfu/mL, how many cfu would there be in 20 μL of dilution tube C? 2) If the absorbance (420 nm) of a 2 mL cell suspension is 0.28 absorbance units, and the cells are dried down to give 0.58 mg dry weight, and a typical cell is 2.9 x 10-13 g dry weight, what was the original density of the culture (in cells/mL)?

Chemistry 1) Take 1 mL of a liquid bacterial culture (aka original culture) and mix it with 9 mL of uninoculated liquid medium in tube A. Take 0.1 mL from tube A and mix it with 9.9 mL of uninoculated medium in tube B. Take 0.2 mL from tube B and mix it with 99.8 mL of uninoculated medium in tube C. Take 0.05 mL from tube C and mix it with 19.95 mL of uninoculated medium in tube D. Take 0.25 mL from tube D and mix it with 99.75 mL of uninoculated medium in tube E. - If the original culture density were 3 x 107 cfu/mL, how many cfu would there be in 20 μL of dilution tube C? 2) If the absorbance (420 nm) of a 2 mL cell suspension is 0.28 absorbance units, and the cells are dried down to give 0.58 mg dry weight, and a typical cell is 2.9 x 10-13 g dry weight, what was the original density of the culture (in cells/mL)?

Chemical Principles in the Laboratory

11th Edition

ISBN:9781305264434

Author:Emil Slowinski, Wayne C. Wolsey, Robert Rossi

Publisher:Emil Slowinski, Wayne C. Wolsey, Robert Rossi

Chapter2: Resolution Of Matter Into Pure Substances, I.paper Chromatography

Section: Chapter Questions

Problem 2ASA

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