Lactose used up Growth on lactose Glucose used up Glucose and lactose added Growth on glucose Time of incubation (hr) FIGURE 7.24 Diauxic Growth Curve of E. coli Growing in a Medium Containing Glucose and Lactose Cells preferentially use glucose. Only when the supply of glucose is used up do cells start metabolizing lactose. Note that the growth on lactose is slower than it is on glucose. Number of cells (logarithmic scale)

Lactose used up Growth on lactose Glucose used up Glucose and lactose added Growth on glucose Time of incubation (hr) FIGURE 7.24 Diauxic Growth Curve of E. coli Growing in a Medium Containing Glucose and Lactose Cells preferentially use glucose. Only when the supply of glucose is used up do cells start metabolizing lactose. Note that the growth on lactose is slower than it is on glucose. Number of cells (logarithmic scale)

Biology 2e

2nd Edition

ISBN:9781947172517

Author:Matthew Douglas, Jung Choi, Mary Ann Clark

Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark

Chapter22: Prokaryotes: Bacteria And Archaea

Section: Chapter Questions

Problem 29RQ: In addition to providing yogurt with its unique flavor and texture, lactic acid-producing bacteria...

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Answer the following questions about the graph below Maltose Lactose Time (hours) (i) (ii) (a) What stage of growth are the E.coli in after 5 hours of culturing? (b) After -5 hr, the lactose concentration in the media is 0, why does this happen? Optical density of culture Relative concentration of lactose and maltose
you grew streak plates of Clostridium sporogenes under both aerobic and anaerobic conditions. Which plates showed bacterial growth, and what does the zone around the metronidazole disc represent? Additionally, explain what types of bacterial growth metronidazole affects and why.
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