Question

Look at the results of the experiment shown in Figure 20-5. Why do you think the different disinfectants are not equally effective against the E. coli bacteria?

http://i.imgur.com/njcJH4v.png

Answer 1

Is it as simple as one disinfectant might be more powerful against the E. Coli?

Answer 2

Yeah I really do think it's that simple.
One disinfectant might be more powerful.

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Here's a fact:

There two types of bacteria:
1. Gram positive
2. Gram negative

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Here's another fact:
E. coli bacteria are Gram Negative bacteria.

What that means is that they're protected by an outer lipid membrane.

If we wanted to kill E. coli bacteria, then we would need to use a disinfectant that could break down that lipid membrane.

You get it?

Answer 3

Yes. Thanks!

Answer 4

Disinfectants act in different ways to combat bacterial growth. Some disinfectants are more effective than other disinfectants at controlling a particular bacterial species. Also, bacteria may develop a resistance to some disinfectants.