AS BIOLOGY P-33

[plantaholic]

I think i got the same
One of the solution had both glucose and reducing sugar but thats just always true since reducing sugar will not be affected by any non reducing test one had starch and i think the enzyme was sucrase since mine hydrolyzed sucrose

we didn't have to name the enzyme, or did we?

 

[plantaholic]

Guys it appears there been a big mix up, some people had results hydrolysing sucrose, some had results hydrolysing starch :s

Mine personally, was hydrolysis of S1, and it couldnt be wrong because i did it like 3 times >_< wth!

And only one biological molecule could be present with each test-tube, but it could be repeated. e.g s1 and s2 both glucose, s3 starch, etc, but never more then 1 molecule in each.

What do we do now about the mix-up? I really don't think my teacher is going to pay any attention to my request -_-

but still, try to bring it to notice

 

[plantaholic]

The question said traces of any biological molecule could be seen in more than 1 solution.. As i remember

yes, but one solution had one molecule only..

 

[Gimmick]

Anyone taking biology p34? If so, any guesses?

 

[Moi]

Guys it appears there been a big mix up, some people had results hydrolysing sucrose, some had results hydrolysing starch :s

Mine personally, was hydrolysis of S1, and it couldnt be wrong because i did it like 3 times >_< wth!

And only one biological molecule could be present with each test-tube, but it could be repeated. e.g s1 and s2 both glucose, s3 starch, etc, but never more then 1 molecule in each.

What do we do now about the mix-up? I really don't think my teacher is going to pay any attention to my request -_-

for me it was hydrolysig S1 but the thing it..it has no glucose nir starch nor sucrose!! my theory is..

that some candidates had diffrent solutions...perhaps because some teachers tell their students what the result should be so cie decided to make diffrent for some so that they will not cheat and WILL HAVE TO do the whole test to know what there answers is...coz if everyone would get the same result...they will simple write what their friends did and not bother testing...

i really do hope am write because am so frightened from this whole mix up since i too got a weird result....

 

[Waleed Amjad]

Well, I got S1 as sucrose , S2 as Starch and S3 as Glucose....

Mine both S1 and S2 got hydrolyzed LOL.... i did 3 times and still the same result....
I think the enzyme was a mixture of two.... which can be Sucrase and Amylase....

Who knows ...InshAllah we will get A's in all our exams..... Good luck everyone...

 

[comrade]

do you have a review like that of AS chemistry?? pls share if can

I don't have any notes on Chemistry. My first exam was Chemistry. It didn't go well. :L I'm sorry for the late reply. Busy with other exams.

 

[comrade]

Oh han me AS k point of view se keh rai thee... Chalo, all the best for P4!

Future may P4 ki ziada weightage hay. Aagay ka bhi soachna chahyay.

 

[comrade]

very important TY man

You're welcome mate.

 

[comrade]

for me it was hydrolysig S1 but the thing it..it has no glucose nir starch nor sucrose!! my theory is..

that some candidates had diffrent solutions...perhaps because some teachers tell their students what the result should be so cie decided to make diffrent for some so that they will not cheat and WILL HAVE TO do the whole test to know what there answers is...coz if everyone would get the same result...they will simple write what their friends did and not bother testing...

i really do hope am write because am so frightened from this whole mix up since i too got a weird result....

How did you get sucrose in S1? I did the non-reducing sugar test. Added HCl then neutralized it and did the benedict's test. There was no change in the colour. Another guy to my side also got the same result. The guy sitting in front of me got sucrose. I did the test two three times. I then confirmed it with the others. Some people had sucrose in their solutions. :s

My ratio was about 4:1. :/ That's wrong I suppose?

 

[comrade]

for me it was hydrolysig S1 but the thing it..it has no glucose nir starch nor sucrose!! my theory is..

that some candidates had diffrent solutions...perhaps because some teachers tell their students what the result should be so cie decided to make diffrent for some so that they will not cheat and WILL HAVE TO do the whole test to know what there answers is...coz if everyone would get the same result...they will simple write what their friends did and not bother testing...

i really do hope am write because am so frightened from this whole mix up since i too got a weird result....

I also didn't get any positive result for sucrose in S1. The guy in front of me got a positive result while the one one my right got a negative result. This is strange. So I did the test about three times just to confirm that no sucrose were present.

 

[Jinkglex]

I think maybe this was a mixture on purpose? to catch cheaters? :O Dun Dun Dunnnn!

 

[ahmed abdulla]

v will have to use the other method...as v need to test enzyme also...for all v knw it cld be denatured due to the heat n stuff...so v ve to be sure...so use the other method....

bro... did any question involving microscope came ... i mean measuring LENGTHS of some specimen of slide using the eyepiece graticule and stagemicrometer PRATICALLY ..not in diagram as in oc/nov2012 ...?
if u can get ur hands on bio paper 34 .. that will be really greatfull !

 

[mannat0033]

any tips for up coming physic MCQ

 

[Moi]

How did you get sucrose in S1? I did the non-reducing sugar test. Added HCl then neutralized it and did the benedict's test. There was no change in the colour. Another guy to my side also got the same result. The guy sitting in front of me got sucrose. I did the test two three times. I then confirmed it with the others. Some people had sucrose in their solutions. :s

My ratio was about 4:1. :/ That's wrong I suppose?

i did not get sucrose either!! i did the benidect test add hcl and neautralized it and still no colour change. i repeated it twice. only me and another girl got these results!! the rest got sucrose but me and her didnt. i answered test three that S1 had non of the biological molecules.

now seeing that many people got this kind of reslult...i think its correct...cie is playing a game with us

 

[mannat0033]

I'm worried about this too, scared that i can't find my specimen under microscope

i think the teacher is suppose to set that up .

 

[Moi]

I think maybe this was a mixture on purpose? to catch cheaters? :O Dun Dun Dunnnn!

think so too

 

[mannat0033]

i did not get sucrose either!! i did the benidect test add hcl and neautralized it and still no colour change. i repeated it twice. only me and another girl got these results!! the rest got sucrose but me and her didnt. i ansered test thre that S1 had non of the biological molecules.

now seeing that many people got this kind of reslult...i think its correct...cie is playing a game with us

you are suppose to let it cool after boiling it with HCL and then neutralise it othewise u wont get positive result .

 

[Moi]

you are suppose to let it cool after boiling it with HCL and then neutralise it othewise u wont get positive result .

i cooled it with cold tap water....

anywayz am not worried anymore as many others got the same thing......i believe cie did three soloutions to get diffrent results and cheating wont occur....otherwise why would they have below test three the statment:

OR
Solution ______ does not have any of the following biological molecules starch glucose and sucrose.

 

[comrade]

i did not get sucrose either!! i did the benidect test add hcl and neautralized it and still no colour change. i repeated it twice. only me and another girl got these results!! the rest got sucrose but me and her didnt. i answered test three that S1 had non of the biological molecules.

now seeing that many people got this kind of reslult...i think its correct...cie is playing a game with us

Hope we're correct. I also filled the tables the wrong way. According to our results, S1 should have been filled in the last table. I filled it in the first one. So I wrote S1 is a non-biological molecule and wrote with black pen for examiner to read. I hope I don't lose marks on that. :/