Q&A - PSLE Science

[tianzhu]

Hi P5G


In primary science, students learn that fishes have gills to help them breathe. Most fishes have scales on their bodies.
Seahorses are fishes. Seahorses have bony plates that help protect their bodies. You may read more about seahorses by following this link.
http://www.indyzoo.com/pdf/Seahorses.pdf

Going by the context in Q13
A ----- Both seahorse and fish have gills.
B ------ Based on picture, both animals have tails. But, there are animals with tails that are not fishes, eg cow, monkey.
C ------ Fishes have scales, but here,some may say that seahorses have bony plates, not scales to protect their bodies.
D ------- Yes, both animals live in the sea. But not all animals living in the sea are fishes eg dolphin

Based on the given options, I’d go for closest option which is (1)

As for Q25, you need to have a good grasp on the modes of dispersal of fruits and seeds. Again, refer to your PSLE Science Guide, fruits and seeds dispersed by wind are dry, light, small and wing like or parachutes structures. Mimosa is classified as dispersal by animals because they have hooks or stiff hairs.

Here the key words in this question is wind dispersed fruits which rules out mimosa(classified as dispersed by animal in PSLE science Guide).Without wind dispersed fruits in this instance, mimosa would be an obvious choice.

In Q25, lalang, angsana and dandelion are wind dispersed fruits. Lalang and dandelion have fruits with fine hairs helping them float, therefore staying for a longer period in the air. I’d more inclined to go for option (2)

Best wishes

[cluelessmom]

Hi all, can anyone tell me wat is the state of matter of Jam? :?

[Muffins]

Hi cluelessmom, strawberry jam is a liquid.


A liquid is a fluid that has the particles loose and can freely form a distinct surface at the boundaries of its bulk material. The surface is a free surface where the liquid is not constrained by a container. And jam can flow freely throughout the bottle without any jams (in this sense, it means blockage) whatsoever, so it is more inclined to being classified as a liquid. That's what I think.....

[cluelessmom]

Thank U Muffins

[Muffins]

No problem!

[rubydoll]

Please answer

Is Mass of a iron rod and a bag of feathers of same weight are same… from
rulang sa1 2009 -q20.

Q}do penguin has wings?from raffles-2009 sa1-book a q1

can anyone pls explain Q-5 from raffles SA1 =2009.
what does a seed need to germinate?does it need oxygen???
thank you

[tianzhu]

Hi


Please follow this link to the testpaper from Raffles.
http://www.misskoh.info/09/primary6-rgssa1-science.pdf

For Q1 ---- Option (2) is correct.
Penguins are birds. They have wings which are used as paddles to help them swim faster, but this information is of no relevance in answering this question.

For Q5 ----- In primary science, students learnt about the three conditions for germination, water, air (oxygen) and warmth ( right temperature).Therefore option (1) is right.

As for Rulang’s question, I can’t find a working link to it. The link in this site malfunctions.
http://www.orlesson.org/orp/ScienceExam.html

Best wishes

[rubydoll]

Thank you.

[ruyu]

State the interdependance of the fish and the hydrilla in this pond community.

[tianzhu]

ruyu:

State the interdependance of the fish and the hydrilla in this pond community.

Hi

Hydrilla(submerged aquatic plant) provides oxygen for fishes when it photosynthesises. Fishes breathe out carbon dioxide that the plants need for photosynthesis. Some fishes find shelter and shade or feed on the plants.The waste from the fishes fertilises the soil to help hydrilla grow.

Best wishes