multiple choice on Pasteur (1 Viewer)

[DepressedPenguino]

In his experiment, Pasteur used specifically designed flasks and broth. What steps would he need to do in order to make this experiment VALID?

(A) pour equal amounts of broth into 2 DIFFERENT types of flask. Boil both flasks for the same time.

OR

(B) pour equal amounts of broth into identical flasks. Boil both flasks for the same time.

 

[DepressedPenguino]

Need a little help with this

 

[MysteryMoon]

Answer: A
Since the experiment is used to test whether air-borne bacteria is the cause of decay in broth, it is the correct procedure to pour broth into DIFFERENT types of flasks.
One would be straight-necked and the other is swan-necked. The bacteria will easily get into straight-necked flask and cause decay, while no bacteria can get into the swan-necked flask.
This is what VALIDITY means. Is it the correct procedure that allows you to get the required results to the hypothesis?

That's why the answer can't be B because you can't really compare results if they're both the same type of flask. It's more related to reliability.

 

[DepressedPenguino]

Answer: A
Since the experiment is used to test whether air-borne bacteria is the cause of decay in broth, it is the correct procedure to pour broth into DIFFERENT types of flasks.
One would be straight-necked and the other is swan-necked. The bacteria will easily get into straight-necked flask and cause decay, while no bacteria can get into the swan-necked flask.
This is what VALIDITY means. Is it the correct procedure that allows you to get the required results to the hypothesis?

That's why the answer can't be B because you can't really compare results if they're both the same type of flask. It's more related to reliability.

My answer was A too but the apparent ans is B off the answer sheet. Is the answer wrong or did pasteur used two 'identical' flasks (i.e both swan-necked) but broke one of the flask's necks when conducting his exp to disprove spontaneous generation?

 

[obliviousninja]

Poor wording. Could be B, ie potentially different results arising of one flask is size of swimming pool, other is size of hand. Ya know wat I mean. Or like something like one flask is made out of xyz material. Obvs all of wat i said is jibberish. But yeah.

I personally woulda gone with A

 

[MysteryMoon]

My answer was A too but the apparent ans is B off the answer sheet. Is the answer wrong or did pasteur used two 'identical' flasks (i.e both swan-necked) but broke one of the flask's necks when conducting his exp to disprove spontaneous generation?

I agree with oblivious ninja. The wording makes the question seem too general. Maybe you can ask your teacher on what he/she thinks.
But the answer sheet could be wrong too so I don't know at this point.