zobia rashid
Badges: 0
#1
Report Thread starter 4 years ago
#1
What should be the control variables for this Investigation and what preliminary investigation can i carry out to choose a suitable value for this investigation
"Extracts from some plants have properties similar to those of medical antibiotics"
0
reply
Lennymuffin
Badges: 0
Rep:
?
#2
Report 4 years ago
#2
(Original post by zobia rashid)
What should be the control variables for this Investigation and what preliminary investigation can I carry out to choose a suitable value for this investigation
"Extracts from some plants have properties similar to those of medical antibiotics"
Variables:
Independent Variable: Types of plant extract
Dependent Variable: Measurements of the space around each disc where no bacteria aregrowing
Controlled Variables: Size of filter paper discs, type of agar,time of incubation

Source: http://sciencegcseisamethods.blogspo...isa-plant.html

Preliminary investigation:Identify the controlled variables:
Size of filter paper discs
Type of agar
Time of incubation

Now choose one that is easy for you to understand, for example the size of filter paper discsToget the marks for this question choose two values for the volume – a big one and a small one would be good:
I will try a filter paper with an area of 5mm^2 and one with an area of 1 cm^2
Saywhat you will do with the filter paper (It isimportant to say what you are going to measure as that is what makes it a controlled variable):

Iwill measure the area for both the filter papers. Iwill addeach of the filter papers to separate agar plates and see which area is best touse. I will measure the area cleared and see which area is clearer and easierto measure

Toget the final mark, say how you will decide which is the best to use:Whicheverareais the easiest to measure accurately thewillbethe best one to choose
Hope this helps
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Regarding Ofqual's most recent update, do you think you will be given a fair grade this summer?

Yes (254)
34.09%
No (491)
65.91%

Watched Threads

View All