Q&A - PSLE Science

[atutor2001]

vidhyalog:

Hi


1) ACS Prelim Science Booklet A - No 17. Can someone pls tell me what is the answer. The given answer is 2. However, my son's teacher told the class that flowers have chloroplasts as well. So he claims the only part without chloroplasts in the root. http://i55.tinypic.com/orsfpv.png\">

The answer (2) is correct because part B is pointed to the petal (not flower).

Do flowers have chloroplast/chlorophyll?
Yes if we consider the sepals which is green in colour.

Are there other parts of a flower (excluding the sepals) that contain chloroplast?
Yes only for a small group of flowers e.g. broccoli, wild flowers with green petals - orchids...

Do flower buds contain chloroplast?
Yes, buds are usually green in colour and have chlorophyll. As they develop, the chlorophyll in the petal will change to other pigment (colour).

Do all roots have no chloroplast?
No some air roots of orchids have chloroplast to make food.

For primary level, lets just accept it as that roots and (non-green) petals have no chlorophyll.

If the word used in the question is \"flower\", then must read the question again carefully.

For the other question on dispersal, I think the given answer is wrong. Should be (2)

[Alchemist]

Nebbermind:

(1) Just learnt that spinal cord is an organ. Thanks to this forum!! But is it taught as such in schools?


(2) Believe that it's taught that flower do not have chloroplast.


(3) Mangrove fruits is also dispersed by water so shd be (4)

Hi Nebbermind -

For (2) I thought so too. But he claims teacher said it does. So wondering if any other teacher has this interpretation.


For (3) Can I then check what type of dispersal does the picture depict. I thought it depicts seed dispersal by water - and as the question asks not the same way as picture - I thought it should be (2). Angsana is by wind and durian is by animals - so does the picture depict seed dispersal by wind and animals?

Thanks

[Alchemist]

atutor2001:

vidhyalog:

Hi


1) ACS Prelim Science Booklet A - No 17. Can someone pls tell me what is the answer. The given answer is 2. However, my son's teacher told the class that flowers have chloroplasts as well. So he claims the only part without chloroplasts in the root. http://i55.tinypic.com/orsfpv.png\">

The answer (2) is correct because part B is pointed to the petal (not flower).

Do flowers have chloroplast/chlorophyll?
Yes if we consider the sepals which is green in colour.

Are there other parts of a flower (excluding the sepals) that contain chloroplast?
Yes only for a small group of flowers e.g. broccoli, wild flowers with green petals - orchids...

Do flower buds contain chloroplast?
Yes, buds are usually green in colour and have chlorophyll. As they develop, the chlorophyll in the petal will change to other pigment (colour).

Do all roots have no chloroplast?
No some air roots of orchids have chloroplast to make food.

For primary level, lets just accept it as that roots and (non-green) petals have no chlorophyll.

If the word used in the question is \"flower\", then must read the question again carefully.

For the other question on dispersal, I think the given answer is wrong. Should be (2)

Thanks atutor. This is a lesson for us adults as well for attention to detail. I would not have interpreted so narrowly as to pointing to petal. I am not sure how much students are drilled in this.

Thanks

[atutor2001]

Nebbermind:

(1) Just learnt that spinal cord is an organ. Thanks to this forum!! But is it taught as such in schools?

During my kids time YES. I remembered in the introductory page of the text book, there was mentioning of what is cell, tissue and organs but most teachers didn't bother to explain.

Something like : cell is the basic unit of live, cell joined together to form tissue and tissue joined together to form organ

Remembered this topic because I had a hard time convincing my kids that skin is an organ and it is the largest organ in the body.

[Verysuperkiasu]

Qn 21 from Pei Chun prelim


The table below shos the number of some organisms living in a habitat.

Organisms No. of Organisms
Slugs ----------- 11
Mynahs -------- 5
Butterflies ---- 6
Ixora ---------- 3
Snails --------- 7
Caterpillars---- 5
Hibiscus ------- 9

How many populations of animals are there altogether?
(1) 4
(2) 6
(3) 7
(4) 34

Answer key is (1) 4 but ds's answer is (2) 6. Which is the correct one?

[Alchemist]

Verysuperkiasu:

Qn 21 from Pei Chun prelim


The table below shos the number of some organisms living in a habitat.

Organisms No. of Organisms
Slugs ----------- 11
Mynahs -------- 5
Butterflies ---- 6
Ixora ---------- 3
Snails --------- 7
Caterpillars---- 5
Hibiscus ------- 9

How many populations of animals are there altogether?
(1) 4
(2) 6
(3) 7
(4) 34

Answer key is (1) 4 but ds's answer is (2) 6. Which is the correct one?

Hi verysuperkiasu,

My son made the same mistake as your daughter. Question is how many population of animals.

[chrisu]

For questions like these, I wonder how should the student answer during PSLE.

vidhyalog:

Nebbermind:

(1) Just learnt that spinal cord is an organ. Thanks to this forum!! But is it taught as such in schools?

(2) Believe that it's taught that flower do not have chloroplast.

[ms_lim]

atutor2001:

ms_lim:

Please help on this question :


http://i56.tinypic.com/2d1u350.jpg\">

Ans key is (1) but my dd explains that D protects the spinal cord so her ans is (3). Is spinal cord a vital organ?

I agree with your dd answer. Spinal cord is an organ as it is made up of tissues (definition of an organ) and it is also a vital one.

Dear atutor2001 :thankyou:

[Nebbermind]

atutor2001:

For the other question on dispersal, I think the given answer is wrong. Should be (2)

oops, didn't noticed the plats at the upstream! :oops:

[Alchemist]

Hi - I have quite a few science queries accumulated from sometime back. Not much luck checking with the Science teacher - so I am posting them here. I thank in advance whoever answers them - and do believe it should help your kids too. Thanks


This is from Rosyth 2010 Prelim. http://i56.tinypic.com/9u2jc0.jpg\">