题目

My LMS Subjects Online quiz 4

多重下拉选择题

Examine the Triple Sugar Iron (TSI) agar tubes in the image below and then answer the questions for Tube A and Tube B. A control tube has been included in the image for comparison.Tube A results:Lactose/sucrose fermentation Blank 1 Question 8[select: , Negative, Positive] Gas from the fermentation of glucose Blank 2 Question 8[select: , Positive, Negative] Hydrogen sulfide (H2S) production Blank 3 Question 8[select: , Negative, Positive] Tube B results:Lactose/sucrose fermentation Blank 4 Question 8[select: , Positive, Negative] Gas from the fermentation of glucose Blank 5 Question 8[select: , Negative, Positive] Hydrogen sulfide (H2S) production Blank 6 Question 8[select: , Negative, Positive]

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思路分析

Question restatement and options being evaluated: - Tube A results: - Lactose/sucrose fermentation: Positive - Gas from the fermentation of glucose: Negative - Hydrogen sulfide (H2S) production: Positive - Tube B results: - Lactose/sucrose fermentation: Negative - Gas from the fermentation of glucose: Positive - Hydrogen sulfide (H2S) production: Negative Now we analyze each option for each tube, explaining what a positive or negative result means in the context of TSI (Triple Sugar Iron) agar. Tube A 1) Lactose/sucrose fermentation (Positive): - A positive result here indicates the organism can ferment lactose or sucrose in the medium. In a TSI tube, lactose and sucrose fermentation typically drives the agar to a yellow color due to acid production (overall acidification of the medium beyond the initial glucose fermentation). This change is often visible as a yellow slant or a yellow entire medium, depending on the organism’s carbohydrate utilization pattern and i......Login to view full explanation