Q&A - PSLE Science

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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Should the answer be A, B and D only?

TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[andante]

atutor2001:

andante:

Hi,

For the question below, can someone help to explain why there will be burn mark on the leaf ? thx

The glass beads are acting like magnifying glass which will converge (focus) the light rays to a point on the leaf surface. The leaf with waxy surface will not get burnt because the smooth surface can reflect the light away. On the other hand, the leaf with hairy surface will absorb the light which will be converted to heat. Accumulation of heat at a single spot caused the surface to get burnt.

Hi atutor2001,
I am wondering how glass beads can act like magnifying glass(convex lens) as it is just like some form of glass material. pls advise. Thx.

[Sun_2010]

P5G:

Please help.


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TIA.

At B

Baking starts once the dough is placed in the oven.

[andante]

atutor2001:

andante:

[quote=\"andante\"]Hi all,

I would like to find out whether the following is structural or behavioural adaptation.
- an earthworm releases mucus to help it slide through the soil quickly when it is threatened.

My DD thought that it is structural adaptation. Pls advise.

Hi,
Can someone help me on the above question ? why ?

Thank you.

My focus is on the word \"releases\" in the question. So my answer will be behavioural adaptation. In other words, I am making an assumption that there are other uses for the mucus.

However, if the statement is changed to \"an earthworm produces mucus which is used only to help it slide through the soil quickly when it is threatened\", I will then pick structural adaptation.[/quote]I am sorry that I don't get what you mean. what is the main difference between \"releases mucus\" and \"produces mucus\" ? Or it is something got to do with voluntary/involuntary action ? i.e. the release of mucus. Thx.