<![CDATA[PSLE Science 2008]]>How did your child find the Science paper ?

]]>https://forum.kiasuparents.com/topic/1139/psle-science-2008RSS for NodeMon, 25 May 2026 17:58:23 GMTTue, 07 Oct 2008 23:32:05 GMT60<![CDATA[Reply to PSLE Science 2008 on Sat, 11 Oct 2008 10:21:02 GMT]]>

lizawa:
caroline3sg:

Lizawa

I originally couldn't get it -- why sugar is the determining factor?
Am I right to say:
Yeast is both a fungi and micro-organism (ie living things). Living things need food (ie sugar is yeast food) and respire. So when carbon dioxide is released, it is this gas that causes the balloon to inflate?

If my son has interpreted the question correctly. Then, sugar is the \"food\" for the yeast. Yeast then undergoes respiration and produces carbon dioxide. The gas (matter) takes up the space in the balloon and so balloon gets inflated.

I asked my P5 child (non-GEP) to attempt this question and he could give me the correct answer, the one regarding sugar being the food for yeast. Curious, I asked her how he 'know' the answer and was told they did experiment with teacher in class before.

I am very sad that my P6 child (GEP) got this answer wrong. He told me he has not done any experiment involving yeast before and also could not recollect being taught this. They are both in the same school and mainstream teachers are different from GEP teachers. Perhaps, they are expected to read up such 'simple' stuff on their own?

The problem with the GEP curriculum is that the kids spent too much time on what is NOT examinable and has no time for learning stuff within the mainstream curriculum. Of course, most will still be able to do well because their parents engaged tutors for them to learn the mainstream stuff on their own. Besides, the kid must have a lot stamina to handle so many projects, assignments, CCAs and other activities and still have time to learn the mainstream syllabus from their tutors.

]]>https://forum.kiasuparents.com/post/8787https://forum.kiasuparents.com/post/8787Sat, 11 Oct 2008 10:21:02 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 08:43:31 GMT]]>

kiasuson:
My son thinks water is also a food for the yeast. Therefore, both balloon will be inflated. His point is that water also contains some inpurities that will be food for the yeast.

If this is a question to test on \"respiration\", the equation for respiration is
sugar + oxygen ---> energy + carbon dioxide + water

I don't know the exact question and the correct answer. This is just my interpretation of what the question is trying to test.

]]>https://forum.kiasuparents.com/post/8666https://forum.kiasuparents.com/post/8666Thu, 09 Oct 2008 08:43:31 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 07:28:49 GMT]]>My son thinks water is also a food for the yeast. Therefore, both balloon will be inflated. His point is that water also contains some inpurities that will be food for the yeast.

]]>https://forum.kiasuparents.com/post/8662https://forum.kiasuparents.com/post/8662Thu, 09 Oct 2008 07:28:49 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 07:23:27 GMT]]>

caroline3sg:
Lizawa

I originally couldn't get it -- why sugar is the determining factor?
Am I right to say:
Yeast is both a fungi and micro-organism (ie living things). Living things need food (ie sugar is yeast food) and respire. So when carbon dioxide is released, it is this gas that causes the balloon to inflate?
If my son has interpreted the question correctly. Then, sugar is the \"food\" for the yeast. Yeast then undergoes respiration and produces carbon dioxide. The gas (matter) takes up the space in the balloon and so balloon gets inflated.

]]>https://forum.kiasuparents.com/post/8661https://forum.kiasuparents.com/post/8661Thu, 09 Oct 2008 07:23:27 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 07:14:46 GMT]]>Lizawa

I originally couldn’t get it – why sugar is the determining factor?
Am I right to say:
Yeast is both a fungi and micro-organism (ie living things). Living things need food (ie sugar is yeast food) and respire. So when carbon dioxide is released, it is this gas that causes the balloon to inflate?

]]>https://forum.kiasuparents.com/post/8660https://forum.kiasuparents.com/post/8660Thu, 09 Oct 2008 07:14:46 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 05:40:09 GMT]]>

caroline3sg:
lizawa
[quote]Becos of the sugar, the yeast will undergo respiration, so produce more gases, hence the balloon will be inflated.
Is this in P6's topic -- respiration?

P5's topic on respiration only mention energy is released when oxygen burns food.

I only know from my secondary sch cookery class that yeast causes flour (in bread, pastry) to rise (I was not from Science stream).[/quote]It should be either P5 or P6, I don't remember. After a while, you just study according to the themes and topics and not the level.

Another parent commented that this question is \"common sense\" question. 🙂 But again how many kids nowadays actually \"bake\" to see that flour rise due to yeast ?

I know there is another question about similarity or differences between the young of cockroach and beetle. One parent commented that too bad the kids nowadays don't live in \"kampongs\", so don't know how the young of a beetle looks like.

]]>https://forum.kiasuparents.com/post/8656https://forum.kiasuparents.com/post/8656Thu, 09 Oct 2008 05:40:09 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 05:23:51 GMT]]>The plants in pot B are overcrowded and therefore inorder to get to expose to a greater amount of sunlight , they have to grow taller to compete with each other.

]]>https://forum.kiasuparents.com/post/8653https://forum.kiasuparents.com/post/8653Thu, 09 Oct 2008 05:23:51 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 03:41:43 GMT]]>Pot A (few seeds) - they absorb more nutrients than Pot B (more seeds), so the former have thick stems.


Pot B, due to the need to fight for nutrients, their stems are thin. Also it is nearer to window, so they fight to get more sunlight.

]]>https://forum.kiasuparents.com/post/8636https://forum.kiasuparents.com/post/8636Thu, 09 Oct 2008 03:41:43 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 03:40:52 GMT]]>one way i’m trying to work this out is to cancel the first negative…


so…

the result of container (B) IS caused by shortage of:

1) space - YES (there is over crowding)
2) sunlight - NO (there is ample)
3) nutrients - YES (lack of because the seeds/plants are competing)
4) CO2 - YES (same as 3)

so… add the negative, the answer should be Sunlight. ??

]]>https://forum.kiasuparents.com/post/8635https://forum.kiasuparents.com/post/8635Thu, 09 Oct 2008 03:40:52 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 03:34:49 GMT]]>I also think the answer is sunlight.

]]>https://forum.kiasuparents.com/post/8633https://forum.kiasuparents.com/post/8633Thu, 09 Oct 2008 03:34:49 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 03:11:51 GMT]]>

Bumblebee135:
The correct question should be like this:


There are two pots of the plant with a different amount of seeds in them, they are put next to each other besode a window. After a few days pot A (fewer seeds), had plants which were short and had thick stems. On the other hand Pot B (more seeds), had plants which were tall and had thin stems. The appearance of the plants in pot B is not due to the lack of _________.

1) space
2) sunlight
3) nutrients
4) carbon dioxide

shouldn't it be sunlight? there's ample amounts as well and equally between both containers...

co2 is not so important during seed germination..., more during plant growth... i'm puzzled...

]]>https://forum.kiasuparents.com/post/8631https://forum.kiasuparents.com/post/8631Thu, 09 Oct 2008 03:11:51 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 02:57:36 GMT]]>lizawa
[quote]Becos of the sugar, the yeast will undergo respiration, so produce more gases, hence the balloon will be inflated.[/quote]Is this in P6's topic -- respiration?

P5's topic on respiration only mention energy is released when oxygen burns food.

I only know from my secondary sch cookery class that yeast causes flour (in bread, pastry) to rise (I was not from Science stream).

]]>https://forum.kiasuparents.com/post/8630https://forum.kiasuparents.com/post/8630Thu, 09 Oct 2008 02:57:36 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 01:29:36 GMT]]>My son’s comment on the paper was that, it may look easy but actually it is difficult. For particular MCQ, the eight students sitting around him, 6 of them got it wrong and the other two he didn’t ask. And he is in a GEP class.

]]>https://forum.kiasuparents.com/post/8624https://forum.kiasuparents.com/post/8624Thu, 09 Oct 2008 01:29:36 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 01:13:39 GMT]]>

jujuboys:
Still cannot understand why does the test tube containing the yeast, sugar and water will inflat the balloon!!!! :x


Is it due to some chemical effects caused by the sugar?
Becos of the sugar, the yeast will undergo respiration, so produce more gases, hence the balloon will be inflated.

]]>https://forum.kiasuparents.com/post/8620https://forum.kiasuparents.com/post/8620Thu, 09 Oct 2008 01:13:39 GMT<![CDATA[Reply to PSLE Science 2008 on Thu, 09 Oct 2008 01:08:48 GMT]]>Still cannot understand why does the test tube containing the yeast, sugar and water will inflat the balloon!!! :x


Is it due to some chemical effects caused by the sugar?

]]>https://forum.kiasuparents.com/post/8618https://forum.kiasuparents.com/post/8618Thu, 09 Oct 2008 01:08:48 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 23:57:27 GMT]]>More details of the paper can be found here.


http://forum.channelnewsasia.com/viewtopic.php?t=184573

The questions were not straight forward and required a lot of thinking.

]]>https://forum.kiasuparents.com/post/8610https://forum.kiasuparents.com/post/8610Wed, 08 Oct 2008 23:57:27 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 23:24:13 GMT]]>

ChiefKiasu:
Bumblebee135:

The correct question should be like this:


There are two pots of the plant with a different amount of seeds in them, they are put next to each other besode a window. After a few days pot A (fewer seeds), had plants which were short and had thick stems. On the other hand Pot B (more seeds), had plants which were tall and had thin stems. The appearance of the plants in pot B is not due to the lack of _________.

1) space
2) sunlight
3) nutrients
4) carbon dioxide

I think the answer should be carbon dioxide as there is plenty of it.

Goodness... will the correct question stand up please?? The double negative \"not due to lack of\" changes the entire question completely. And yes, if this is the actual question, the answer should be carbon dioxide.

Reminds me of the game where a story gets passed on to one person to another and how the different the final message can become. 🙂

And yet people don't think the exam was difficult?

Yes, I asked my son what was his answer for this question. He told me was \"carbon dioxide\", then I asked what was the question. He said the question was asking for \"not cause by\". So depends on how you interpret the question during the exam. If you have read too fast, or not detail enough, you could miss the important part.

So again, looks easy, but tricky and need to think before you answer.

]]>https://forum.kiasuparents.com/post/8606https://forum.kiasuparents.com/post/8606Wed, 08 Oct 2008 23:24:13 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 14:58:49 GMT]]>

Bumblebee135:
The correct question should be like this:


There are two pots of the plant with a different amount of seeds in them, they are put next to each other besode a window. After a few days pot A (fewer seeds), had plants which were short and had thick stems. On the other hand Pot B (more seeds), had plants which were tall and had thin stems. The appearance of the plants in pot B is not due to the lack of _________.

1) space
2) sunlight
3) nutrients
4) carbon dioxide

I think the answer should be carbon dioxide as there is plenty of it.
Goodness... will the correct question stand up please?? The double negative \"not due to lack of\" changes the entire question completely. And yes, if this is the actual question, the answer should be carbon dioxide.

Reminds me of the game where a story gets passed on to one person to another and how the different the final message can become. 🙂

And yet people don't think the exam was difficult?

]]>https://forum.kiasuparents.com/post/8590https://forum.kiasuparents.com/post/8590Wed, 08 Oct 2008 14:58:49 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 14:51:07 GMT]]>The correct question should be like this:


There are two pots of the plant with a different amount of seeds in them, they are put next to each other besode a window. After a few days pot A (fewer seeds), had plants which were short and had thick stems. On the other hand Pot B (more seeds), had plants which were tall and had thin stems. The appearance of the plants in pot B is not due to the lack of _________.

1) space
2) sunlight
3) nutrients
4) carbon dioxide

I think the answer should be carbon dioxide as there is plenty of it.

]]>https://forum.kiasuparents.com/post/8588https://forum.kiasuparents.com/post/8588Wed, 08 Oct 2008 14:51:07 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 12:49:19 GMT]]>Hi kiasuson,


Hope this helps. The yeast question in today's PSLE Science paper :

http://www.1800-teacher.com/forums/showthread.php?p=2208#post2208

]]>https://forum.kiasuparents.com/post/8577https://forum.kiasuparents.com/post/8577Wed, 08 Oct 2008 12:49:19 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 09:35:20 GMT]]>jujuboys

It is not true to say plants breathe on carbon dioxide. They take in carbon dioxide during photosynthesis (during the day or when there is sunlight / light). Don’t forget plants respire too. So during respiration, plants need oxygen.

]]>https://forum.kiasuparents.com/post/8564https://forum.kiasuparents.com/post/8564Wed, 08 Oct 2008 09:35:20 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 09:11:06 GMT]]>[quote]I don't know if this question is complete. But another parent told me the question asked which balloon will be inflated more ?


From all these discussion, I think most questions really need more thinking than just putting the most \"obvious\" answer down. So tricky paper indeed ![/quote]I think u are right. Anyway, I do not want to ask my son anymore. He has another HCL paper tomorrow. Thanks

]]>https://forum.kiasuparents.com/post/8560https://forum.kiasuparents.com/post/8560Wed, 08 Oct 2008 09:11:06 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 09:08:24 GMT]]>

kiasuson:
Another question: There are two contianers with a inflated Balloon on top. One container is mixed with Yeast, Sugar and Water and the other container is mixed with Yeast and Water. Which container will pump up the balloon? My son answer both.

I don't know if this question is complete. But another parent told me the question asked which balloon will be inflated more ?

From all these discussion, I think most questions really need more thinking than just putting the most \"obvious\" answer down. So tricky paper indeed !

]]>https://forum.kiasuparents.com/post/8559https://forum.kiasuparents.com/post/8559Wed, 08 Oct 2008 09:08:24 GMT<![CDATA[Reply to PSLE Science 2008 on Wed, 08 Oct 2008 08:49:30 GMT]]>

kiasuson:
I think the question is not so easy. My son recap that it is a question with 2 pots showing different number of seeds. One with only two and the other with a few. They also show the effect after a few days. One with big roots and the other crowded pots with small roots but tall plants. From this, they ask what the experiment shows and which factor affect the results.


1) water
2) sunlight
3) nutrients
4) carbon dioxide

My son choose Nutrients because of the small roots...
My child also has another version of the 'same' question; one involving food-web.

]]>https://forum.kiasuparents.com/post/8557https://forum.kiasuparents.com/post/8557Wed, 08 Oct 2008 08:49:30 GMT