Biology paper 62 confusion

[shafayat]

the female reproductive organs are always less than males in every specie ...

 

[venecia]

i was confused in the question as they asked about how to find if there are 2 different carbohydrates and bananas dot contain starch

 

[Chucky]

i was confused in the question as they asked about how to find if there are 2 different carbohydrates and bananas dot contain starch

simple, ones a reducing sugar test, where you crush a sample and mix benedicts solution in a test tube. you heat the test tube in a water bath
the others a starch test, and starch is a carbohydrate! make the same sample by crushing and add iodine solution this time
results :
for reducing sugar test it will go from blue to orange or red brick
for starch test it will go from brown to blue black

note: you must mention the change in colour as in "brown to blue black" instead of just "blue black"
don't know if crushing and preparing a sample is all in the process but i included it just in case, and lucky me cause i found out i lost 6 marks in this thread.

 

[Alaa Hassan]

simple, ones a reducing sugar test, where you crush a sample and mix benedicts solution in a test tube. you heat the test tube in a water bath
the others a starch test, and starch is a carbohydrate! make the same sample by crushing and add iodine solution this time
results :
for reducing sugar test it will go from blue to orange or red brick
for starch test it will go from brown to blue black

note: you must mention the change in colour as in "brown to blue black" instead of just "blue black"
don't know if crushing and preparing a sample is all in the process but i included it just in case, and lucky me cause i found out i lost 6 marks in this thread.

U Lost 6 marks Where? And What about the labels.. Are they right..?

 

[venecia]

but how can you give starch test if banana contains no starch and so the test will be negative and hence it will not be proved that banana contains 2 different carbohydrates

 

[venecia]

simple, ones a reducing sugar test, where you crush a sample and mix benedicts solution in a test tube. you heat the test tube in a water bath
the others a starch test, and starch is a carbohydrate! make the same sample by crushing and add iodine solution this time
results :
for reducing sugar test it will go from blue to orange or red brick
for starch test it will go from brown to blue black

note: you must mention the change in colour as in "brown to blue black" instead of just "blue black"
don't know if crushing and preparing a sample is all in the process but i included it just in case, and lucky me cause i found out i lost 6 marks in this thread.

i mean bananas dont contain starch so how will the test be positive

 

[mohamad yassine]

IT is in the opposite order

 

[Fatima_Toomii]

About naming the flower parts, the anthers should be availabe in larger quantaties to provide many pollen grains, while you only need one stigma for the pollen grain to land on (Also, since it was an insect-pollinated plant, the insects would need to rub against the anthers so the pollen grains will stick to them while they feed on the nectary, yeah? But by looking at the picure, don't you think it would be kind of hard for the insect to rub against the "anther" that is placed higher than the "stigma") :/ Also, the stigma is ususally found at a higher level than the anthers to prevent self-pollination.

 

[Fatima_Toomii]

i mean bananas dont contain starch so how will the test be positive

Bananas DO have starch

 

[Afraah]

just gave paper 62 today, so this confusion is directed to those who have the same variant.
the last question ie. number 3, where we had to label the floral reproductory organs, i put mine in this order:

A > style
B > stigma
C > filament
D > anther

turns out me and just another friend are the only ones who put it in this order, while 99% of the others put it in the exact opposite order.

But i feel this one's right, and that there were many carpels and only one long male reproductive organ, because the stigmas all seemed to be small and inside the petals.

post your answers with logic here please

Uhm hi...
Technically this is how i went for it ---> A) Filament , B) Anther ... C) Style... D)Stigma
Cz uhm what holds the anthers is called a filament... and in the pic its those ones that are like ''shorter'' than that very one which was long... now bout the long one ( C/D) ... C is the style becuse inside it's a pollen tube that transfers the pollen whch was on D ( the stigma) to the tube which is in C ( the style ) =)
That's how i looked at it lOl

 

[Chucky]

ofcourse bananas have starch didn't you ever eat one?

 

[wooowooowoo]

ofcourse bananas have starch didn't you ever eat one?

LOL! Epic comment is epic.

 

[Gimmick]

I've another question: What was the diagram labeling of the ant's head? (The ant was a Meat Ant, according to the references)

 

[Afraah]

I've another question: What was the diagram labeling of the ant's head? (The ant was a Meat Ant, according to the references)

Pair of antennae
Compound Eyes
Fangs ( teeth like structures ) <-- that's ALL I culd get ahah :S

 

[Mustafa omar]

What r the most important question in pp3 nd most common questions ??

 

[Afraah]

What r the most important question in pp3 nd most common questions ??

Look at the Syllabus for 2012 Biology the supplement section u need to know the answers to those the supplement section holds 70% of paper 3

 

[Chucky]

Look at the Syllabus for 2012 Biology the supplement section u need to know the answers to those the supplement section holds 70% of paper 3

has this worked for other science subjects as well?

 

[Afraah]

has this worked for other science subjects as well?

Im not sure for physics, bt yes ive actually seen it in Chemistry! bt hey! dont like NOT study the core section to u cnt like apply ur knwldge to supplement without known the basics, Core

 

[Chucky]

yeah yeah, i started by solving all the core papers before i got to the supplementary section.
i've just been looking through the 2010 question papers and they seem a bit more difficult than average, and there's a lot of remembering to do, so any cambridge document that pin points what REALLY helps if studied is useful, just to calm the nerves down

 

[Afraah]

yeah yeah, i started by solving all the core papers before i got to the supplementary section.
i've just been looking through the 2010 question papers and they seem a bit more difficult than average, and there's a lot of remembering to do, so any cambridge document that pin points what REALLY helps if studied is useful, just to calm the nerves down

hahahh i must say, good luck ;P