Tutor Niedino: Pri Science Questions and Concepts

[atutor2001]

Nebbermind:

Oh...so what combi wld u have chosen?

At first I also pick A, B, C. As there is no such combination, I starts to question B because personal knowledge tells me that plants can also grow from spores (which I am not suppose to use for experimentation). My guess is A & C.

[I_belive]

atutor2001:

I_belive:

Hi,
I would like to know the answer too. I guess (3) is correct.

Thank you. This question is from \"old school.com\" Question 14, which my friend asked me.

http://www.oldschool.com.sg/index.php/module/PublicAccess/action/Wrapper/sid/ea5f3768e0dae62aa6d01beee8123931/cmbn_id/1936/qba/1

Their given answer is (2) but I don't agree with it. Can share with us why you have not included (B)?

Why B is not included,

I think from the experience, I can get conclusion that \"Seeds can grow into plants.\" But not clue that \"Plants MUST come from seeds\". That is why I think B should not be included.

[atutor2001]

I_belive:

Why B is not included,

I think from the experience, I can get conclusion that \"Seeds can grow into plants.\" But not clue that \"Plants MUST come from seeds\". That is why I think B should not be included.

Thank you, I think that solved my doubts.

[Nebbermind]

yeah…note your point that ‘seed -> plant’ and cannot conculde the other way.

[atutor2001]

Nebbermind:

yeah...note your point that 'seed -> plant' and cannot conculde the other way.

When I told my friend the explanation she said :

Ya! \"My hubby has mustache.\" is not the same as \"Has mustache is my hubby.\" :lol:

[Nebbermind]

atutor2001:

Nebbermind:

yeah...note your point that 'seed -> plant' and cannot conculde the other way.

When I told my friend the explanation she said :

Ya! \"My hubby has mustache.\" is not the same as \"Has mustache is my hubby.\" :lol:

I'm more looking at the way the phrase is structured. Had it been \"The plants came from seeds\", it wld qualify as TRUE.

[beepeebful]

these conflict in statements can be solved by apply logic and science concepts. sometimes if your child still does not understand, you could employ the use of venn diagrams!

[ctct61t]

Niedino:

Hi Tianzhu,


Using logical thinking (a science process skill) boiled water does not contain oxygen (a common examination question is that why do fish not survive when they are put into cooled boiled water). The bubbles in boiling water can then be attributed to hot water vapour (which is steam, since there is a conversion of liquid to solid state) and some dissolved air in the water (the dissolved air in the water gains heat and hot air rises). So out of the 4 options,

(1) Hot water vapour
(2) Hot water droplets
(3) Air dissolved in the water
(4) Only oxygen is released from the hot water

Option (1) is the best answer and options (2) and (4) are misconceptions.
There may or may not be dissolved air in the water, hence option (2) is not as suitable an answer as option (1).

Just a side note, air is a composite mixture of gases, so this again lends itself to many misunderstandings.

As for question 2, again this is a question that's not set very well, since steam is technically hot water vapour. I would assume that the best answer is steam.

Hope it helps

Option 3 is the right answer.

this question is let us know, air is disolved in water during normal temperature. when the water is boiled, the air solubility is reduced by its aggregasive heat movement, thus air come out from water when the wate was boiled at 100 C. after water fully boiled, the bigger bubbles will be full of hot water vapor.

[24hr-mum]

is plastic made of things that were once alive (i read from a guide bk that is it made from crude oil whc come from remnants of living things that died long ago), or is it made from things nvr alive?


what does moss and fern feed on? is it feed on living things?

can they make their own food since they are plants?

is yeast a fungi or a kind of micro-organism just like bacteria?

[atutor2001]

24hr-mum:

is plastic made of things that were once alive (i read from a guide bk that is it made from crude oil whc come from remnants of living things that died long ago), or is it made from things nvr alive?


what does moss and fern feed on? is it feed on living things?

can they make their own food since they are plants?

is yeast a fungi or a kind of micro-organism just like bacteria?

Wow your questions are very interesting.

1. Part of the components for making plastic comes from crude oil (which is once alive). However, in Pr sch, kids are taught that plastics are made from things that are never alive because the crude oil itself has been changed/broken down into a different chemical compound before it can be made into plastic i.e. the original chemical structure of crude oil itself cannot be made into plastic. (unlike say wood for making furniture, we do not need to change the chemical structure of wood before making the furniture)

2. The word \"feed\" is ambiguous. Animals feed on others to get \"food\" and \"nutrients\". (\"food\" is to provide energy while \"nutrient\" is to provide raw materials for growth) However, plants do not \"feed\". Plants can make its own food and absorb nutrients from the ground. For moss and fern that grow on other living things e.g. trees, they still make their own food but they absorb nutrients from the living things that they grow on. If \"feed\" is to mean the process of absorbing nutrients, then we can say that ferns and moss \"feed\" on living things provided the picture shows them growing on a living thing. They can also \"feed\" on the ground.

3. Yeast is a single-cell organism and cannot be seen with our naked eyes. Micro-organisms are living things that we cannot see with our naked eyes. Therefore, yeast is a micro-organism.

Regards