Paper Discusion: Bio/52 & /51

[Malik777]

/51? :S

what were the two independant variables for q2?

 

[Oishee Asif]

/51? :S

Nah, she's from PK. She did 52.

 

[joanna omar]

Lemme just tell you the questions we had because, honey, I ain't got no idea what you talking about.

1. ELECTROPHORESIS; same species of invertebrate, 4 different varieties of genetic fingerprint
Use of RNA Probes, how it works
Why is this method used for DNA fingerprinting, for detecting one nucleotide change?
Outline electrophoresis and amplification
Controlled variables
Then we had this photo of 3 DNA fingerprints, we had to draw arrows where all the varieties matched up in all 3, which ones were in a pair
Then we had another question but I forgot...

2. SORGHUM, treated with green manure using legumes with roots, shoots or both
Use of t-test
Describe what "p < 0.05" means
Describe what "statistically significant" means
Controlled variables
Things which would be uncontrollable
Then they gave us these two tables, with "significant" or "not significant", we had a 6 mark question for a conclusion on treating with green manure -_-
Then from one of the tables, we had to find the increase of something and the ratio of something..

It probably sounds easier than your paper, but trust me: the sorghum question was SO HARD for us, whereas the electrophoresis question wasn't too bad. Al7amdulillah

What was ur answers in each of them ?

 

[Malik777]

/51? :S

one was concenteration of Nitrogen and other I dont remember :/

 

[Oishee Asif]

What was ur answers in each of them ?

Just so you know, I'm a complete idiot. Warning given.

Electro:

1. RNA probes are either radioactive or fluorescent to mark the specific DNA fragments, and select them thereafter. The DNA samples are cut using restriction enzymes, forming double-stranded fragments. These are heated and treated such that single-stranded fragments are left with sticky ends, which are complementary to the RNA probes. The RNA probes are single-stranded, and when these probes are mixed with the fragments, they are selected.

2. As the slightest change in the sequence can be picked up (single change in one nucleotide), this could be used for genetic screening. Frame shifts, silent mutations, base deletions, substitutions, additions can be found, blah blah...

3. I wrote so much, my hand broke.

4. pH, voltage.

5. I drew a horizontal line through A, so all my arrows were in line with that. The one that cut through A had all 4 varieties.

6. Varieties 1 & 2.

Sorghum: *swears internally*

1. Normal distribution. Continuous data.

2. I messed this question up.

3. Messed this up too.

4. Time (1 month) left before experiment began, forgot the other one

5. Conc of nitrate ions already present in soil, amount of water in soil

6. I think I wrote:
From table 2.2, overall plant showed significant differences when treated with both roots and shoots, the diff was not due to chance; from table 2.2, roots showed no significant difference; from table 2.1, mean dry mass increased for whole plant when used with any treatment.

7. 44.1%, 3

8. OH and null hypothesis: The use of green manure had no effect on the sorghum or something like that ;_;;;;

(And hehe. Wrote 'Electro'. Spidey's enemyyyy. Such a nerd I am. Lalala)
http://static2.hypable.com/wp-conte...azing-spider-man-2-villain-electro-poster.jpg

 

[Oyessorzo]

As None of the error bars overlap, so the difference in the two values is significant, so we can say the student's experiment was reliable because as we decrease the nitrogen the enzyme's activity also decreases. (I can be wrong, this is what I wrote)

i wrote that too

 

[joanna omar]

Just so you know, I'm a complete idiot. Warning given.

Electro:

1. RNA probes are either radioactive or fluorescent to mark the specific DNA fragments, and select them thereafter. The DNA samples are cut using restriction enzymes, forming double-stranded fragments. These are heated and treated such that single-stranded fragments are left with sticky ends, which are complementary to the RNA probes. The RNA probes are single-stranded, and when these probes are mixed with the fragments, they are selected.

2. As the slightest change in the sequence can be picked up (single change in one nucleotide), this could be used for genetic screening. Frame shifts, silent mutations, base deletions, substitutions, additions can be found, blah blah...

3. I wrote so much, my hand broke.

4. pH, voltage.

5. I drew a horizontal line through A, so all my arrows were in line with that. The one that cut through A had all 4 varieties.

6. Varieties 1 & 2.

Sorghum: *swears internally*

1. Normal distribution. Continuous data.

2. I messed this question up.

3. Messed this up too.

4. Time (1 month) left before experiment began, forgot the other one

5. Conc of nitrate ions already present in soil, amount of water in soil

6. I think I wrote:
From table 2.2, overall plant showed significant differences when treated with both roots and shoots, the diff was not due to chance; from table 2.2, roots showed no significant difference; from table 2.1, mean dry mass increased for whole plant when used with any treatment.

7. 44.1%, 3

8. OH and null hypothesis: The use of green manure had no effect on the sorghum or something like that ;_;;;;

(And hehe. Wrote 'Electro'. Spidey's enemyyyy. Such a nerd I am. Lalala)
http://static2.hypable.com/wp-conte...azing-spider-man-2-villain-electro-poster.jpg

Thanks alot
Aha its okay sorghum Q was such a mess .....Inshsllah khier

How abt the define part ?
and what ensured the reability of sorghum exp ?

 

[Oishee Asif]

Thanks alot
Aha its okay sorghum Q was such a mess .....Inshsllah khier

How abt the define part ?
and what ensured the reability of sorghum exp ?

I screwed up the define part :'( Asta3'firullah, Nauzobillah ;_;_;_;

And the reliability... What was the exact question? I think I forgot

 

[GCE As and a level]

GUYS what was the answer for these questions in BIOLOGY/9700/paper 11
1- Which process is the least affected by a change in the fluidity of the membrane ?
2-What is the MINIMUM number of membranes that are crossed by oxygen and carbon dioxide molecules ?
3-some thing about the hemoglobin protein structure ( I think that which of the protein structures of the hemoglobin are codded by DNA or some ting like this )
THNX

 

[Oishee Asif]

GUYS what was the answer for these questions in BIOLOGY/9700/paper 11
1- Which process is the least affected by a change in the fluidity of the membrane ?
2-What is the MINIMUM number of membranes that are crossed by oxygen and carbon dioxide molecules ?
3-some thing about the hemoglobin protein structure ( I think that which of the protein structures of the hemoglobin are codded by DNA or some ting like this )
THNX

o.o
This thread is for Paper 51 and 52. :3

 

[GCE As and a level]

o.o
This thread is for Paper 51 and 52. :3

IF U DONT WANT TO HELP U CAN IGNORE IT
and some people did 11 and 51 for biology

 

[Oishee Asif]

IF U DONT WANT TO HELP U CAN IGNORE IT
and some people did 11 and 51 for biology

I don't wanna ignore it, I'm not mean or anything—but Malik777 started this thread for P51 and P52. :S
There are designated threads for P11, man.

 

[IbtiCool]

Just so you know, I'm a complete idiot. Warning given.

Electro:

1. RNA probes are either radioactive or fluorescent to mark the specific DNA fragments, and select them thereafter. The DNA samples are cut using restriction enzymes, forming double-stranded fragments. These are heated and treated such that single-stranded fragments are left with sticky ends, which are complementary to the RNA probes. The RNA probes are single-stranded, and when these probes are mixed with the fragments, they are selected.

2. As the slightest change in the sequence can be picked up (single change in one nucleotide), this could be used for genetic screening. Frame shifts, silent mutations, base deletions, substitutions, additions can be found, blah blah...

3. I wrote so much, my hand broke.

4. pH, voltage.

5. I drew a horizontal line through A, so all my arrows were in line with that. The one that cut through A had all 4 varieties.

6. Varieties 1 & 2.

Sorghum: *swears internally*

1. Normal distribution. Continuous data.

2. I messed this question up.

3. Messed this up too.

4. Time (1 month) left before experiment began, forgot the other one

5. Conc of nitrate ions already present in soil, amount of water in soil

6. I think I wrote:
From table 2.2, overall plant showed significant differences when treated with both roots and shoots, the diff was not due to chance; from table 2.2, roots showed no significant difference; from table 2.1, mean dry mass increased for whole plant when used with any treatment.

7. 44.1%, 3

8. OH and null hypothesis: The use of green manure had no effect on the sorghum or something like that ;_;;;;

(And hehe. Wrote 'Electro'. Spidey's enemyyyy. Such a nerd I am. Lalala)
http://static2.hypable.com/wp-conte...azing-spider-man-2-villain-electro-poster.jpg

I messed up the first one completely..... I thought the probe was what had complementary bases and wrote about that :/ I never read about it before though. And for the gel electropherosis I just wrote like 5 lines..... The fragments are placed on agarose gel, which is then placed on a conductive buffer. A voltage is applied to the buffer and the DNA fragments move to the anode ad they are negative. The lightest fragment travels the farthest. I though this was enough for 5 marks. I might be wrong because I've had 0 practical experience and wrote all this because I'm studying chemistry too. The Green Manure wasn't that hard though....

 

[GCE As and a level]

I don't wanna ignore it, I'm not mean or anything—but Malik777 started this thread for P51 and P52. :S
There are designated threads for P11, man.

IF U DONT WANT TO HELP AND I F U DIDNT LIKE MY POST HERE,THEN U CAN IGNORE IT
and some people did 11 and 51 for biology
i THINK ITS BETTER TO STOP THAT

 

[tanixx]

one was concenteration of Nitrogen and other I dont remember :/

type of species of maize..what experiments did you underline in q2 like x and y or z and z ?

 

[tanixx]

and how was the maize experimnet reliable?

 

[tanixx]

Answers: (I can be wrong)

a)i) To hydrolyse lipids as detergents contain Enzymes Lipase.

ii) To Denature the enzymes

iii) To seperate the Debris of peas from the DNA mixture.

iv) To hydrolyse proteins associated with DNA like histone.

b) After treating with Restriction enzymes, place the 3 samples on three different agrose Gel. place it at Cathode(-ve) and apply the potential difference. The fragments will move to the anode, depending on their size/mass. smaller mass fragment will move the farther and larger will move the smallest distance. Use the DNA probes to identify the Fragments./markers. You can use neuliotide containing Radioactive phosphate. The complimentary neucliotides would combine with each other. and DNA bands are visible on the photographic film. Repeat this at least thrice. This experiment is a low risk/ electric shock and its precaution.

c)i) Numbers of different size of DNA fragments

ii) Temperature and concentration/volume of restriction enzyme.

d)i) Number of Bands for REsEnzi are greater than the bands from ResEnz22.

ii) DNA treated with both of the restriction enzymes is having more number of bands than the respective samples treated with only one restriction enzyme.

iii)Insufficient samples there should be one sample which is first treated with REsEnzi and then with Res Enz 2.

d)i) I started from the right end of the electrogram and used the complimentary bases.

couldnt the temperature increase be to break the hydrogen bonds?

 

[Oishee Asif]

I messed up the first one completely..... I thought the probe was what had complementary bases and wrote about that :/ I never read about it before though. And for the gel electropherosis I just wrote like 5 lines..... The fragments are placed on agarose gel, which is then placed on a conductive buffer. A voltage is applied to the buffer and the DNA fragments move to the anode ad they are negative. The lightest fragment travels the farthest. I though this was enough for 5 marks. I might be wrong because I've had 0 practical experience and wrote all this because I'm studying chemistry too. The Green Manure wasn't that hard though....

Both the probes and DNA fragments have complementary sequences, you're not wrong! You'll get a mark for that, don't sweat.
Example: the light is off. That means it's dark. You could also say: it's dark here. Which means that the light is off. Both are right, right?

And don't worry. If you don't get full marks for that, you will get minimum 3.

 

[Malik777]

couldnt the temperature increase be to break the hydrogen bonds?

No Hydrogen bonds aint so weak to be broken by just 60^C :/

 

[Oishee Asif]

Thanks alot
Aha its okay sorghum Q was such a mess .....Inshsllah khier

How abt the define part ?
and what ensured the reability of sorghum exp ?

Just remembered.
Reliability was so that all of the plots had the same starting point. No biased growth. Everything was taken account to from the same moment.