Q&A - PSLE Science

[atutor2001]

P5G:

Please help.


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TIA.

(a) Part A will grow new shoots while part B will wither and die.

(b) Part A has roots to absorb water and nutrient from the ground. It also has food stored in its stems and roots. Therefore, it can grow new shoots.

Part B has leaves which allow water vapour from part B to be released through the stomata. However, it does not have roots to absorb water. With water being lost continuously through the leaves, part B will wither and die.

[atutor2001]

P5G:

Please help.


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TIA.

M is plants
N is decomposition.

Decomposition is important because it helps to break down dead organisms into simple substances which are nutrients for the plant. Otherwise, the world will be filled with dead organisms.

[atutor2001]

P5G:

Please help.


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TIA.

Electrical energy of copper coil
Chemical potential energy of capacitor
Heat and light energy of bulb

(I think this is also out of syllabus)

[atutor2001]

htn:

need help, Rosyth preliminary 2010


Q22. A block of ice is put in a sealed plastic box.The box is then placed in the middle of a classroomon a hot day.

What will happen to the temperature of the melting ice, the water and the air in the box after some time?


Temperature of

melting ice water air in the box

1.remains the same increases decreases
2.decreases remains the same increases
3.remains the same decreases decreases
4.increases remains the same increases

what is the ans?

TIA

I will pick (1)
However, if the ice and water is in a small container (e.g. glass), then the temperature of the water will remain at 0 degree C.

[atutor2001]

P5G:

Please help.


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TIA.

A and G are important because they are the food producer which all other organisms in the community depends on either directly or indirectly for food and energy.

B obtains energy directly from the producer A & G but D obtains energy directly only from G. Energy from A is transferred to D indirectly through F & E and some energy is lost along the way. Therefore, the total amount of energy of organisms B will be more than the total amount of energy of organisms D. This implies that the number of organism B will be more than D. Therefore, C will consume more organism B than D.
(this is correct only if the physical size of each B and D are about the same - technically this question is wrong)

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[atutor2001]

P5G:

Please help.


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TIA.

a) green lace wing flies because they help to get rid of aphids

b) For sudden drop in population size, remember the following causes :

(i) drought / famine
(ii) disease
(iii) introduction of predators
(iv) migration (seasonal)
(v) change from larva to pupa etc.

Use them in the order above.

[atutor2001]

P5G:

Please help.


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TIA.

The spirometer measures volume of air that enters and leaves the lungs.

Graph is showing volume of air on the y-axis.

Although it is not stated on the axis we can quite safely interpret that the graph is showing the volume of air inside the lungs because it never reaches zero (if volume of air is zero, the lungs collapsed which causes death).

Therefore, B is exhaling as the volume of air in the lungs decreases.

[ms_lim]

Hi, can you help to explain this question? Ans key is 1 but my dd's ans is 4 :

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