Q&A - P3 Science

[tianzhu]

Hi


One observes that the difference between set up X and set up Y is that the Petri dish Y contains sugar.

Based on the given data, one can see that the bacteria growth in dish Y is increasing as highlighted by the number of plus signs (+) as compared to dish X which stays the same.

So, one can infer that sugar helps bacteria growth.

I’d choose sugar. The bacteria growth is increasing in dish Y as compared to dish X which remains the same. It shows that sugar speeds up bacterial growth.

Best wishes

[rrjan]

thanks for your kind response, tianzhu

[cimman]

tianzhu:

Hi


One observes that the difference between set up X and set up Y is that the Petri dish Y contains sugar.

Based on the given data, one can see that the bacteria growth in dish Y is increasing as highlighted by the number of plus signs (+) as compared to dish X which stays the same.

So, one can infer that sugar helps bacteria growth.

I’d choose sugar. The bacteria growth is increasing in dish Y as compared to dish X which remains the same. It shows that sugar speeds up bacterial growth.

Best wishes

yes, sugar is a substance that promotes growth in living organisms. It is used primarily used as an energy source. Leaves in plant produces glucose for food, in humans, we burn glucose for energy too.
Of course, too much of glucose and the excess gets stored as fat. So, those with a sweet tooth, lay off the sweets and less fat will accumulate.

[shirley.020816tamzil]

Hi all


Need help with the part b of the below questions
http://i51.tinypic.com/j9n9fk.jpg\">

Answer given by answer sheet was that when the rubber sheet is pulled down, air from the surrounding will draw air through the plastic tube and inflate the balloons.

I don't really understand the answer, can anyone clarify?

[veraclari]

Dear Parents,


Am trying to get my P3 kid interested in Science. Anyone has simple - do at home - experiments to recommend?

I've tried dissolving sugar and Melting of ice, planting seeds. Anything else you can recommend?

Thanks In Advance!!!

[tianzhu]

shirley.tamzil:

I don't really understand the answer, can anyone clarify?

Hi

In answering this question, a student needs to have knowledge of the human respiratory system.

It’s helpful to read your textbook or guidebook(MC) to get some brief notes about the parts and functions of the respiratory system.

The diagram in the question shows the balloon model of a lung in a bottle.
The plastic tube acts as a windpipe and air tubes. The balloons resemble the lungs. The rubber sheet acts as a diaphragm and the inside of the bell jar represents the chest cavity.

When the rubber sheet is pulled downwards, the volume of the inside of the bell jar is increased. This decreases the air pressure inside bell jar so it is lower than the air pressure of the surrounding air. As air flows from a region of higher pressure to a lower pressure region, air flows through the plastic tube into the balloons, thus inflating them.

This is similar in nature when we are breathing in or inhaling.

Hope this helps.

Best wishes

[shirley.020816tamzil]

tianzhu:

shirley.tamzil:

I don't really understand the answer, can anyone clarify?

Hi

In answering this question, a student needs to have knowledge of the human respiratory system.

It’s helpful to read your textbook or guidebook(MC) to get some brief notes about the parts and functions of the respiratory system.

The diagram in the question shows the balloon model of a lung in a bottle.
The plastic tube acts as a windpipe and air tubes. The balloons resemble the lungs. The rubber sheet acts as a diaphragm and the inside of the bell jar represents the chest cavity.

When the rubber sheet is pulled downwards, the volume of the inside of the bell jar is increased. This decreases the air pressure inside bell jar so it is lower than the air pressure of the surrounding air. As air flows from a region of higher pressure to a lower pressure region, air flows through the plastic tube into the balloons, thus inflating them.

This is similar in nature when we are breathing in or inhaling.

Hope this helps.

Best wishes

Thanks for the clear explanation.

[tianzhu]

rrjan:

thanks for your kind response, tianzhu

Hi

You're welcome.

Best wishes

[tianzhu]

shirley.tamzil:

Thanks for the clear explanation.

Hi

You're welcome.

Best wishes

[smartmummy]

veraclari:

Dear Parents,


Am trying to get my P3 kid interested in Science. Anyone has simple - do at home - experiments to recommend?

I've tried dissolving sugar and Melting of ice, planting seeds. Anything else you can recommend?

Thanks In Advance!!!

i did these in kindergarten.Again with my DD she in k1,so my son also see.May we can go beyond than that,my son attempt make a circuit with two lemons but failed.We did use battery and made successfully a simple circuit when he was in pri 1.

U can make volcano using vinegar and baking soda.If you mix together in a bottle then the bubble come out from the bottle.