Q&A - P3 Science

[atutor2001]

tony:

Hi AnnT2009,


Atutor2001, I thought \"everywhere\" means literally everywhere, like every single place? Merriam-Webster's Online Dictionary has \"Everywhere\" defined as \" in every place or part\", and \"Every\" is defined as \"being each individual or part of a group without exception\".

\"Everywhere\" can have a few uses. For example, \"Trees are found everywhere in Singapore.\" would mean that trees can be found in alot of places but not every single place. Similarly, \"There was blood everywhere at the crime scene\" cannot imply that every inch of the place is covered by blood.

Maybe you can try checking with \"Collin Cobuild\". I like this dictionary because it gives the most comprehensive examples on different uses for each word.

[Lynn2]

Hello All


I have a science question from the following link, question 5
http://www.wendykoh.com/06/primary4-rgs-science.pdf

May I know what is the relationship between the number of sumberged plant and the amount of soil being washed into the pond.

Can someone explain to me what they are looking for when talking about soil being washed into the soil?

thanks

rgds
Lynn2

[tianzhu]

Hi


Under the old science syllabus, a little bit of water pollution is covered under the topic on Water in P4.I am not sure about the current syllabus.

Concept
When soil is washed into the pond, water becomes muddy or cloudy. It blocks sunlight from reaching the submerged water plants; therefore they cannot carry out photosynthesis to make food. They may wilt and eventually die, leading to decrease in the number of submerged water plants.

Use the concept
Figure 1 shows that the number of submerged water plants decreases as the amount of soil washed into the pond increases. Therefore it is correct.

In figure 2, the number of submerged water plants is not affected by the amount of soil washed into the pond. Hence it is incorrect.

Figure 3 is offside. It shows that the number of submerged water plants increases as the amount of soil washed into the pond increases.

Figure 4, at any number of submerged water plants, the amount of soil washed remained constant. Hence, it’s wrong.

Option(1) is the correct answer. Hope this helps.

[tianzhu]

Hi, Dharma and Full.Cream


There are some missing information in one of my previous post.Here is the revision.Please follow this link.

http://www.oldschool.com.sg/index.php/module/PublicAccess/action/Wrapper/sid/a1d5550a35132f7d768a9cd73d70318e/mcq_id/15658

I am sorry for the inconvenience.

[acforfamily]

Hi, appreciate your help on this question from Henry park p3 SA2 paper


Characteristics of a plant x
- it bears fruit
- it grows on land
- it does not have branches

Which statement / (s) is correct?

a) it is a palm
b) it is a fern
c) it is a flowering plant

Is it (a) and or
only ?
(b) is incorrect as ferns do not bear fruit
is correct as flowering plants bear fruit

[watmekiasu]

acforfamily:

Hi, appreciate your help on this question from Henry park p3 SA2 paper


Characteristics of a plant x
- it bears fruit
- it grows on land
- it does not have branches

Which statement / (s) is correct?

a) it is a palm
b) it is a fern
c) it is a flowering plant

Is it (a) and (c) or
only (c)?
(b) is incorrect as ferns do not bear fruit
(c) is correct as flowering plants bear fruit

I recall dd doing this question some time ago. In the assesment book , it mentioned that palm trees do not have branches (tho I still find it hard to believe).

[Lynn2]

Hello Tianzhu

Thanks for your crystal clear concept and explanation.

For the same paper,that is rgs06 paper. I have one more question, and that is question 8.

Function of stomata is for the exchange of gases.But why is the answer is to prevent too much water from being lost to its surroundings.May I know how this gases thingy linked to sunlight.

Thanks again

rgds

tianzhu:

Hi

Under the old science syllabus, a little bit of water pollution is covered under the topic on Water in P4.I am not sure about the current syllabus.

Concept
When soil is washed into the pond, water becomes muddy or cloudy. It blocks sunlight from reaching the submerged water plants; therefore they cannot carry out photosynthesis to make food. They may wilt and eventually die, leading to decrease in the number of submerged water plants.

Use the concept
Figure 1 shows that the number of submerged water plants decreases as the amount of soil washed into the pond increases. Therefore it is correct.

In figure 2, the number of submerged water plants is not affected by the amount of soil washed into the pond. Hence it is incorrect.

Figure 3 is offside. It shows that the number of submerged water plants increases as the amount of soil washed into the pond increases.

Figure 4, at any number of submerged water plants, the amount of soil washed remained constant. Hence, it’s wrong.

Option(1) is the correct answer. Hope this helps.

[Lynn2]

Here is the link for question 8


http://www.wendykoh.com/06/primary4-rgs-science.pdf

Thanks

rgds
Lynn2

[tianzhu]

Hi


In primary science, students learn that plants photosynthesise in the presence of light to make food. They also respire at all times. During photosynthesis, oxygen is given out and carbon dioxide is taken in. Plants take in oxygen and give out carbon dioxide when they respire. When stomata open, water is lost through a process called transpiration (evaporation of water through the leaves).The gaseous exchanges are done through tiny openings called stomata. There are more stomata on the undersides of leaves.

In answering Q8, we’ve to note the key words.

Under very strong sunlight for a long time, these openings will eventually close.

On a hot sunny day plants could become dehydrated as they lose water. Therefore, stomata close to prevent the plants from losing too much water.
Option(4) is correct.

What I’ve covered is very basic, the opening and closing of stomata is far more complex.You can find out more by reading books on Biology and Botany. Also try doing searches on Yahoo/Google.

Best Wishes

[Dharma]

tianzhu:

Hi, Dharma and Full.Cream


There are some missing information in one of my previous post.Here is the revision.Please follow this link.

http://www.oldschool.com.sg/index.php/module/PublicAccess/action/Wrapper/sid/a1d5550a35132f7d768a9cd73d70318e/mcq_id/15658

I am sorry for the inconvenience.

SorryTianzhu, I missed this out earlier.

When the cardboard is removed, the light brown gas will spread to fill up the whole of the jar and flask.

This tells us that
1.\tGas has no definite shape – it takes up the shape of the container that it is in.
2.\tGas has no fixed volume – it spreads to fill up the space in the flask in addition to the space it has already filled in the jar.

The answer is Option C – B & C

# Although air can be compressed but the experiment does not demonstrate this property of air.