How was bio p51?

[marz_katy]

They information mentioned seeds use 1-10 MICROmoles, not millimoles.

how much will i lose if it ws micro?

 

[Ashique]

how much will i lose if it ws micro?

It was 1 mark per limitation. The improvement was for 2 marks I think.

Which two of the given data did you underline for the t test? I selected 2 years and 6 years, and 3 years and 6 years, since the difference in the duration was large, and other factors could have affected the results.

And what did you write for the absolute last one?

 

[marz_katy]

i

It was 1 mark per limitation. The improvement was for 2 marks I think.

Which two of the given data did you underline for the t test? I selected 2 years and 6 years, and 3 years and 6 years, since the difference in the duration was large, and other factors could have affected the results.

And what did you write for the absolute last one?

confirmed with a friend and she said shes oversure it ws milli...andt-test i chose 6 months and 2 yrs and 6 mnth and 3 years i gues bcuz dr error bar for 2 yr and 3 year dint overlap so der ws significant difference...and da last 1 im sure im wrng

 

[Ashique]

i
confirmed with a friend and she said shes oversure it ws milli...andt-test i chose 6 months and 2 yrs and 6 mnth and 3 years i gues bcuz dr error bar for 2 yr and 3 year dint overlap so der ws significant difference...and da last 1 im sure im wrng

The error bars not over lapping- isn't that the answer to the third last question? That the data is reliable to make comparisons since the bars don't over lap?

 

[Ashique]

i
confirmed with a friend and she said shes oversure it ws milli...andt-test i chose 6 months and 2 yrs and 6 mnth and 3 years i gues bcuz dr error bar for 2 yr and 3 year dint overlap so der ws significant difference...and da last 1 im sure im wrng

Oh and what about the factors to be constant and the control?
I wrote:
Constant: Temp and pH
Control: a 1 g sample with anaerobic bacteria ( I have no idea for this one)

 

[marz_katy]

The error bars not over lapping- isn't that the answer to the third last question? That the data is reliable to make comparisons since the bars don't over lap?

Reliability is checked by seeing how big or small the error bars are..if error bar is small da relability is more and if big reliability is less

 

[marz_katy]

Oh and what about the factors to be constant and the control?
I wrote:
Constant: Temp and pH
Control: a 1 g sample with anaerobic bacteria ( I have no idea for this one)

i rote ph/temp(one of them i dnt remember) and sample of soil form same area

 

[marz_katy]

Oh and what about the factors to be constant and the control?
I wrote:
Constant: Temp and pH
Control: a 1 g sample with anaerobic bacteria ( I have no idea for this one)

control i took plastic beads:$ im not even sure

 

[Irfan1995]

I'll try to post the answers I remembered, but I'm not sure if they're all correct:
1) Provide a procedure: Pretty much the exact same one given, but I also mentioned carrying out (serial) dilution to provide concentrations from 0 - 3 mmol (0 mmol serves as a control). To increase the reliability, I mentioned tabulating the results (drawing a table) or drawing a best-fit line in addition to repeating at least 3 times and taking a mean (after discarding anomalous results). As a safety precaution, I mentioned taking care while cutting the seeds and wearing gloves (as iodine and/or GA might be irritants)
Independent variable: concentration of GA/mmol.dm^-3 (units have to be mentioned)
Dependent variable: area of the brown region/cm^2 (hence the activity of amylase/t^-1)
Limitations: Here are the ones I've mentioned:

• Amylase is limited by rate of diffusion and availability of substrate (starch)
• Shape of the brown area might be irregular, so it's difficult to measure accurately
• Different seeds contain different concentrations of amylase constituents

Fixing an error: I chose the second option. I mentioned that we could carefully place some (translucent) graph paper on top of the Petri dish. Since paper contains starch, it will be stained blue-black and brown as well. If this is not the case, carefully draw an outline of the brown region with a pencil. Count the number of squares and blah blah blah...
2) Explain the trend of bacteria after 6 months: as you go deeper, the pressure exerted (by the soil particles) increases. This clogs up the soil and prevents any gas diffusion. Ergo oxygen cannot reach the bottom of the soil hence aerobic bacteria would die of starvation. Anaerobic bacteria will thrive due to the reduced competition.
Controlled variables: possible answers include temperature, pH, volume of soil etc...
Control: take a sample of soil and sterilize it (with chlorine or antibiotics). This sample will not contain any bacteria which serves as a control.
Is the data reliable?: Error bars at 6 months and 2 years are reliable as the length of the error bars is short. (The opposite is true for the other data)
Choosing two t-test means: 6 months and 3 years and 6 months and 6 years (I can't remember the numbers exactly, but they were the only two bars that don't overlap)
Reason: they don't overlap
How to find the dehydrogenase activity at "X": draw a line of regression (best-fit line) of all the points. Find the point on the line that corresponds to "X" and find the corresponding abscissa.

 

[menna1234]

for the t-test i chose 6month and 2 years, and 2 years and 6 years, while the reason is that the error bars didn't overlap

 

[marz_katy]

for the t-test i chose 6month and 2 years, and 2 years and 6 years, while the reason is that the error bars didn't overlap

t

I'll try to post the answers I remembered, but I'm not sure if they're all correct:
1) Provide a procedure: Pretty much the exact same one given, but I also mentioned carrying out (serial) dilution to provide concentrations from 0 - 3 mmol (0 mmol serves as a control). To increase the reliability, I mentioned tabulating the results (drawing a table) or drawing a best-fit line in addition to repeating at least 3 times and taking a mean (after discarding anomalous results). As a safety precaution, I mentioned taking care while cutting the seeds and wearing gloves (as iodine and/or GA might be irritants)
Independent variable: concentration of GA/mmol.dm^-3 (units have to be mentioned)
Dependent variable: area of the brown region/cm^2 (hence the activity of amylase/t^-1)
Limitations: Here are the ones I've mentioned:

• Amylase is limited by rate of diffusion and availability of substrate (starch)
• Shape of the brown area might be irregular, so it's difficult to measure accurately
• Different seeds contain different concentrations of amylase constituents

Fixing an error: I chose the second option. I mentioned that we could carefully place some (translucent) graph paper on top of the Petri dish. Since paper contains starch, it will be stained blue-black and brown as well. If this is not the case, carefully draw an outline of the brown region with a pencil. Count the number of squares and blah blah blah...

2) Explain the trend of bacteria after 6 months: as you go deeper, the pressure exerted (by the soil particles) increases. This clogs up the soil and prevents any gas diffusion. Ergo oxygen cannot reach the bottom of the soil hence aerobic bacteria would die of starvation. Anaerobic bacteria will thrive due to the reduced competition.
Controlled variables: possible answers include temperature, pH, volume of soil etc...
Control: take a sample of soil and sterilize it (with chlorine or antibiotics). This sample will not contain any bacteria which serves as a control.
Is the data reliable?: Error bars at 6 months and 2 years are reliable as the length of the error bars is short. (The opposite is true for the other data)
Choosing two t-test means: 6 months and 3 years and 6 months and 6 years (I can't remember the numbers exactly, but they were the only two bars that don't overlap)
Reason: they don't overlap
How to find the dehydrogenase activity at "X": draw a line of regression (best-fit line) of all the points. Find the point on the line that corresponds to "X" and find the corresponding abscissa.

the aerobic and anaerobic one...i said as the depth witht 0m has photosynthesisng plants there is high concenration of oxygen gas and as the depth increases the concentration of oxygen decreases due to the absence of plants there...is ds acceptable?

 

[jose machado]

You guys the very last question on q2 It was to find the mean since the mean as i learnt in stats is a prediction of a population and u could see that all the activities were the activities for 1g of soil by finding the mean activity per 1 gram u would be estimating !