Biology Paper 52 Discussion

[notgeek]

how do u do the DNA extraction process frm the algal leaf

 

[WhiteAngel]

I did the same but the pigment was S
the chi square i got the same

 

[WhiteAngel]

how do u do the DNA extraction process frm the algal leaf

i have the same question !!!
But thoose were Pigments not DNA !

 

[Romeo10]

how do u do the DNA extraction process frm the algal leaf

i have the same question !!!
But thoose were Pigments not DNA !

I think the extraction would be by grinding up with sand and mix with water and add a known suitable volume to the starting line which was drawn by PENCIL ( insoluble )

 

[Romeo10]

Can please guys tell me will I take the full marks in the procedure question as I mentioned the following :
1. Grinding up with sand to get the extract and mix it with water.
2. Draw a pencil line which is the starting line.
3. Add a known volume of the solvent which would be as for example ETHANOL and ensure that it is beneath the starting line.
4.Then wait till there would be solvent front so as the solvent travelled to the end of the strip and by the way I mentioned the use of silica gel strip as a Chromatography Paper.
5.Then measure the distance moved by the solvent front and the distance travelled by each seperated pigment by Vernier Calipers or a Ruler.
6.THen I mentioned the procedure given which tells that you use 2 solvents so I have mentioned this also.
7.Control Temperature by a thermostatic water bath or a well controlled room temperature.
8.Repeat using different strains from Same species of algae and repeat 3 times for each strain, exclude anomalous values, calculate average and apply statistics.
9. Make the volumes and the concentrations of solvents and the extract the same in each repeat.
10.It is a low risk investigation and may be the solvent is flammable such as ETHANOL so avoid approaching it from heat or fire.
This is that I have written in the procedure which was out of 8 marks .. Will I get the full mark ( 8/8) and if there is a deduction of marks how many marks deducted ??

Also another question what did you do in the question of how the data to plot the absorption spectra (Without algae 100 % transmission)??
and the next question what are data needed to plot the action spectra??
and what are the 2 variables to control in the first question I said 1. Concentration and volume of suspension of algae. 2. Volume of Water
Is this right ??
Thanks In advance

 

[Science]

Guys the process of extracting photosynthetic pigments from chlorophyll is written in Mary Jones' study guide under the photosynthesis chapter! She has stated that it was to be done through TLC.

 

[Mia4005]

okay sigh, maybe ill get marks for the other stuff i rote, the conditions, low risk experiment bla bla
4 marks maybe?

 

[Romeo10]

Guys the process of extracting photosynthetic pigments from chlorophyll is written in Mary Jones' study guide under the photosynthesis chapter! She has stated that it was to be done through TLC.

I didnt hear anything about the TLC you are saying, I have written the extraction by Grinding up with sand and mix it with water and my teacher told me that the method I said is right so can you please read the procedure I wrote and tell me how many marks I will gain??

 

[Mia4005]

guys i din rite the sand grinding thing, i just rote to crush, filter and use the filtrate , coz the pigments are present in it
would i still get mark for the rest?
is it rong

 

[Science]

I'm not really sure. This same question was in biology P4 and I attempted it using the method you have stated above using paper chromatography. But then I saw that the study guide had mentioned use of TLC so that's what I wrote in P5.

 

[Mia4005]

its 8 marks, like even if my topic was rong, do u thnk they will give me marks for how i formated it?