Tutor Niedino: Pri Science Questions and Concepts

[Leanne]

Hello Niedine


Thanks for clarifying .

For processing skill both needed in mcq and section b, do u have a recommended guide book for both?thank you.

Best wishes
Leanne

Niedino:

Hi MOE H, Leanne & Vanilla,

Just to clarify, the emphasis on Primary Science is on process skills, especially with the content reduction in the new syllabus. Hence, it is important to teach your children to identify the types of thinking needed. For a list of thinking processes, you may refer to the Science
syllabus.

From the questions you have posted Vanilla, I assume that your child has difficulty with inference and deductive questions. Here's the thinking that should be going on in your child's mind when attempting the question.

E.g. Why did the predators decrease more than the aphids? Perhaps they are not the predators of aphids. Perhaps the habitat is not suitable for them. (MOE H, they might be eating each other so it's not impossible)

E.g Why did the leaf not have bubbles? Perhaps the stomata is blocked? The leaf might have been plucked sometime ago and cannot photosynthesize.

E.g what makes the insecticide work? The water is contaminated so how does that get into the food?

Inferring is basically a series of intelligent
guesses based on the knowledge given in the question.

Leanne, the equation is very simple and there are no molecular quantities, it's just to prepare the pupils

Hope this helps

[caroline3sg]

[quote]From the questions you have posted Vanilla, I assume that your child has difficulty with inference and deductive questions. Here's the thinking that should be going on in your child's mind when attempting the question.


E.g. Why did the predators decrease more than the aphids? Perhaps they are not the predators of aphids. Perhaps the habitat is not suitable for them. (MOE H, they might be eating each other so it's not impossible)

E.g Why did the leaf not have bubbles? Perhaps the stomata is blocked? The leaf might have been plucked sometime ago and cannot photosynthesize.

E.g what makes the insecticide work? The water is contaminated so how does that get into the food?

Inferring is basically a series of intelligent
guesses based on the knowledge given in the question. [/quote]Vanila Cake is a secondary student. She is concerned for her younger sister.

BTW, under what circumstances would the stomata be blocked?

Such 'intelligent guesses\" would be taught in class?

[Niedino]

caroline3sg:

[quote]From the questions you have posted Vanilla, I assume that your child has difficulty with inference and deductive questions. Here's the thinking that should be going on in your child's mind when attempting the question.


E.g. Why did the predators decrease more than the aphids? Perhaps they are not the predators of aphids. Perhaps the habitat is not suitable for them. (MOE H, they might be eating each other so it's not impossible)

E.g Why did the leaf not have bubbles? Perhaps the stomata is blocked? The leaf might have been plucked sometime ago and cannot photosynthesize.

E.g what makes the insecticide work? The water is contaminated so how does that get into the food?

Inferring is basically a series of intelligent
guesses based on the knowledge given in the question.

Vanila Cake is a secondary student. She is concerned for her younger sister.

BTW, under what circumstances would the stomata be blocked?

Such 'intelligent guesses\" would be taught in class?[/quote]Hi Caroline,

Yes, the process skills should be taught in school. The stomata can be blocked by a layer of oil as mentioned in earlier postings.

VanillaCake, apologies as I did not read through all the postings so addressed you wrongly But you mentioned that the PSLE Science would be more interesting this year. I would agree and I would also add that with content reduction, there will be a higher emphasis on process skills so we have to be more careful with the two keystones in the Primary Science curriculum, Concepts and Process Skills.

[Niedino]

Leanne:

Hello Niedine


Thanks for clarifying .

For processing skill both needed in mcq and section b, do u have a recommended guide book for both?thank you.

Best wishes
Leanne

Well, a guidebook will suffice. Process skills have to be cultivated so questioning must become a habit. Do not discourage when your kids question. Allow the inquiry to continue and guide them in their thinking so that when they face a problem seemingly unsolvable, they will be equipped to handle them. You may want to take a look at some critical thinking books e.g. Richard Paul to help you understand reasoning better.

[harish_thiyagrajan.023307hotmail.023307com]

Niedino:

Hi Tianzhu,


To respond to the earlier question, again, this does not show that air can be \"compressed\". It shows that air has no definite shape and no definite volume. I would go for option (C). As for the movement of the gas upwards, since air can be compressed (thus resulting in higher pressure), air can also be \"stretched\" (thus resulting in lower pressure). Opposite of compression is tension.

Another way to look at it is that compression is a \"push\", while tension (stretching) is a \"pull\". So the movement of brown air upwards into the round space shows that air can be \"stretched\" since the air was \"pulled\" to fill a bigger container, not \"pushed\" into a smaller container like compression.

This is just my opinion. Some answer keys may justify that since you can show that air can \"stretch\", you can also infer that air can be \"compressed\" but I do not subscribe to this logic.

Hope it helps.

I agree. I think it is C. :lol:

[Leanne]

Thanks.

Can I know what is the title of the book by richard paul?

Niedino:

Leanne:

Hello Niedine

Thanks for clarifying .

For processing skill both needed in mcq and section b, do u have a recommended guide book for both?thank you.

Best wishes
Leanne

Well, a guidebook will suffice. Process skills have to be cultivated so questioning must become a habit. Do not discourage when your kids question. Allow the inquiry to continue and guide them in their thinking so that when they face a problem seemingly unsolvable, they will be equipped to handle them. You may want to take a look at some critical thinking books e.g. Richard Paul to help you understand reasoning better.

[starlight1968sg]

Leanne:

Hi everyone


Am new to the forum and trying to learn as much as I can to help my ds.

I have been trying to understand into the details of this simple equation and hope someone can help to get it right.thanks

Carbon dioxide + Sunlight + Water => Sugar + Oxygen.

LHS is for photosynthesis to take place, RIGHT hand side as in sugar, can someone pls explain how starch and sugar link into this?thanks alot.

caroline3sg:

[quote]When the insect eat the leaves, how does it know it is eating the food carrying tubes only and not the water carrying tubes?The food and water carrying tubes are the transport system, how does the insect differentiate them?

Photosynthesis is carried out on the leaves (that's where chlorophyll is). So the leaves would have water, using this formula :
Carbon dioxide + Sunlight + Water => Sugar + Oxygen.

Food carrying tubes flow downwards, I mean the nutrients.

Water carrying tubes flow upwards, I mean the water.

[/quote]Thanks Neidino and others who have responded to my question.

The food made by plants is usually (or loosely at the primary school's level) referred to as sugar but the more appropriate term is glucose.

http://en.wikipedia.org/wiki/Glucose

http://en.wikipedia.org/wiki/Starch

\"In photosynthesis, plants use light energy to produce glucose from carbon dioxide. The glucose is stored mainly in the form of starch granules, in plastids such as chloroplasts and especially amyloplasts. Toward the end of the growing season, starch accumulates in twigs of trees near the buds. Fruit, seeds, rhizomes, and tubers store starch to prepare for the next growing season.\"

During photosynthesis, glucose is produced which eventually stored as starch. To test starch ie presence of food made by the green leaves, use an iodine solution.

In addition, water carrying tubes ie xylems are uni-directional ie upward but food carrying tubes ie phloems are bi-directional ie both upward and downward.

Science is such interesting and amazing!

[caroline3sg]

starlight

Thank you for pointing out food carrying tubes are 2 directional. I was too eager to show one up and one down, although at the back of my mind I know nutrients from the soil also go upwards.

[livewith_vanilla]

In my opinion,mindmaps are better. No it does not mean one line=one sentence, two lines=two combined sentences and so on. You have to note the marks. If the question is like asking:


a)Who is correct, John or Ben? (1m)

________________________________________________________
________________________________________________________

U are given two lines, but ur ans can be just sweet and short.

a)Who is correct, John or Ben? (1m)

John is correct.___________________________________________
_______________________________________________________


Explain the answer given in (a). (2m)

________________________________________________________
________________________________________________________


U are given 2 lines, but the marks awarded in 2 marks,hence you must fully explain why.

Explain the answer given in (a). (2m)

Plants can only carry out photosynthesis when there is a light source, taking in carbon dioxide and giving out oxygen. However, when no light is present, plants will carry out respiration and take in oxygen while giving out carbon dioxide.

My explanation might require more than 2 lines, but if it fully explains why, then you will be awarded 2 full marks. So it doesn't mean that if given more lines, must use up all the lines.

[atutor2001]

caroline3sg:

starlight

Thank you for pointing out food carrying tubes are 2 directional. I was too eager to show one up and one down, although at the back of my mind I know nutrients from the soil also go upwards.

Hi caroline3sg

There are many past exam questions, asking \"What do the upward and downward arrows (drawn next to a plant) represent?\"

Such questions give the children the wrong impression that food only travels downwards. Had to tell my kids in those days that those upward arrows, (especially those above branches with leaves) can be \"food\". However, to avoid confrontation, they were told to put the answer as \"water\". Hopefully such question does not appear anymore.

Incidentally, brown stem can also carry out photosynthesis because if we scrape away the external brown layer, there is chlorophyll behind it.