Three different strains of Escherichia coli, respectively A, B, and C have been inoculated in threedifferent media, namely I, II, and III, and the growth of each bacterial strain has been followed byspectrophotometry (Figure 1).Strain AStrain BStrain C4.545Medium I43.5252.53E 2.5Minimal medium+ Glucose252.5O 1510.5as05100200300400500600100200400600200Time (minjStrain AStrain BStrainB4.54s4sMedium II3.515252 3Minimal252medium+ Glucose1+ Arginine0.5asas100200300400500600100300400s00600100300400600TmeTime (min)Strain AmeStreinBStreine4.54545Medium II44.3.53.5252 3Minimal medium+ Glucose5 2.525258 1515+ Lactose10.5050510020030040050060030020040010200300630Time (min)Tine iminTime minFigure 1. Growth curves of the three E. coli strains A, B and C in three media: I, minimal mediumcontaining glucose; II, minimal medium containing glucose and arginine; and III, minimalmedium containing glucose and lactose. The graphs represent the variations of optical densityrelated to time.11- Explain why the measurement of absorbances can be used to monitor the growth ofbacterial populations. Provide another method that could be used for the same purpose.Optical DensityCstial DeruityCatial DenstyOptical DertyGatial Density

E.coli cells take around 20 mins to replicate themselves. The replication of bacteria is an…

Three different strains of Escherichia coli, respectively A, B, and C have been inoculated in three different media, namely I, II, and III, and the growth of each bacterial strain has been followed by spectrophotometry (Figure 1). Strain A Strain B Strain C 4.5 Medium I 3.5 25 2.5 Minimal medium + Glucose 0.5 100 200 300 400 50 100 200 00 600 10 200 00 Tme tmtnt Strain A met StrainB Strain B 4.5 Medium II 3.5 Minimal medium 1.5 + Glucose + Arginine 05 200 300 50 600 200 600 Strain A Strein Streine 4.5 45 Medium II 3.5 2.5 Minimal medium + Glucose + Lactose 100 200 300 400 50 600 100 200 00 sa 10 200 Time (min) Tine imin Time min Figure 1. Growth curves of the three E. coli strains A, B and C in three media: I, minimal medium ontaining glucose; II, minimal medium co medium containing glucose and lactose. The graphs represent the variations of optical density hing glucose and arginine; and III, minimal related to time. 1 1- Explain why the measurement of absorbances can be used to monitor the growth of bacterial populations. Provide another method that could be used for the same purpose.

Three different strains of Escherichia coli, respectively A, B, and C have been inoculated in three different media, namely I, II, and III, and the growth of each bacterial strain has been followed by spectrophotometry (Figure 1). Strain A Strain B Strain C 4.5 Medium I 3.5 25 2.5 Minimal medium + Glucose 0.5 100 200 300 400 50 100 200 00 600 10 200 00 Tme tmtnt Strain A met StrainB Strain B 4.5 Medium II 3.5 Minimal medium 1.5 + Glucose + Arginine 05 200 300 50 600 200 600 Strain A Strein Streine 4.5 45 Medium II 3.5 2.5 Minimal medium + Glucose + Lactose 100 200 300 400 50 600 100 200 00 sa 10 200 Time (min) Tine imin Time min Figure 1. Growth curves of the three E. coli strains A, B and C in three media: I, minimal medium ontaining glucose; II, minimal medium co medium containing glucose and lactose. The graphs represent the variations of optical density hing glucose and arginine; and III, minimal related to time. 1 1- Explain why the measurement of absorbances can be used to monitor the growth of bacterial populations. Provide another method that could be used for the same purpose.

Biochemistry

9th Edition

ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

Section: Chapter Questions

Problem 1P

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