Final+Revision

I'm picking up some points from the topics that you must note - THIS DOES NOT COVER EVERYTHING AND YOU MUST STILL STUDY YOUR NOTES

Also, the SA Revision Paper is a good indication of the types of questions that may come out... do your corrections for the paper and REVISE IT!

__**Primary 4 Topics - Heat and Light**__ IT IS CRUCIAL that you attempt the Heat Revision Worksheet and use the Answer Key provided. Points to note on the worksheet: Remember the evaporation question? Which evaporates the fastest? It seems obvious to you now since we have gone through this... so how about the set-up below? Which evaporates faster? HINT: Take out a ruler and measure the exposed surface area ! Don't be lazy! Use the ruler!!

Note also the last question: It asks you which material is best for keeping ice from melting the fastest... If you look at the graph, set-up F loses heat the least - it is a good insulator of heat ... As such, the answer is the material for Set-up F! Insulators are good for keeping things warm, AND also good for keeping things cold! Why?

__**Photosynthesis and Respiration**__ Do read up on what is photosynthesis and respiration, and what raw materials are needed for the reactions and what are the products and by-products?  __** Food Chain, Food Web and Decomposition **__ We've done much on Food Chain and Food Web, but do read up on DECOMPOSITION! Decomposers are very important living things that feed on dead organisms - note that though they are feeding on dead matter, they are still LIVING organisms, they respire and live like any other living thing!

**__Reproduction __** Do look at our notes again...

__Circulatory and Respiratory Systems __ While marking your worksheets on this topic, I realised some of you are unable to make comparisons between the oxygenated blood flowing away from the lungs and the deoxygenated blood flowing to the lungs. Also, comparing between inhaled air and exhaled air.... Do look at your worksheet again and revise.

**__Electrical Systems__** I've gone through tonnes of revision on this... do revise!

__Water Cycle __ Also another topic that we've thoroughly revised... most of this topic is closely tied to Heat. Do revise Heat Gain and Heat Loss concept as this is one of the crucial points for this topic... when heat gain happens, the surroundings or object in contact loses heat, and vice versa - when heat loss happens, the surroundings gain heat or object in contact gains heat... Heat gain and heat loss happens as long as there is a temperature gradient - a difference in temperature between two objects or an object and its surroundings

Room temperature - what is room temperature? Do note that the temperature of the surroundings (room temperature) dictates heat loss OR heat gain as discussed in the point above.

HAPPY REVISING!  <span style="font-family: 'Arial Black',Gadget,sans-serif;">