There's a lot of things we need to know when sitting for Biology paper 3. It may be difficult or easy depends on how much tips you know about it.
1. Dilution
There are 2 types of dilutions: simple dilution and serial dilution
Use the formula m1v1 = m2v2 to calculate
If it is simple dilution, you need to know the total volume of solution, volume of ____ solution and also volume of distilled water.
Volume of ____solution can be found by using the formula m1v1 = m2v2 while volume of distilled water is found by : total volume of solution - volume of _____
For serial dilution, remember to draw arrows and labelled the arrows with correct volume and concenration.
2. Table
First column must be independent variable and subsequents columns are dependent variables.
Remember UNITS!
Common mistake when recording the data :
-NO decimal places for time taken. Eg. for second, write 1 but not 1.0.
-NEVER write no colour change.
-ALWAYS write both the initial and final colour change.
-Compare the darkness of the colour of solution. Eg. you can use word like slightly darker/ paler OR ____ is paler than ____ but darker than ____.
*Be careful if the questions ask you to replicate the experiment, that's mean you need to have another column of data and another column for the average data.
3. Risks and Hazards
Risk: low/ medium/ high
Hazard: the item name
4.Set up control
-Solutions
replace _____solution with (same volume) of distilled water.
-Enzyme
replace enzyme with (same volume) of distilled water
5. Standardized variables
Standardize means kept constant / controlled, which means, you need to set up a controlled variable.
-Volume of solutions
Use a syringe to standardize the volumes at ___ml for each test
-Temperature
Use thermostatically controlled water bath to standardize the temperature at __
-Mixing solutions
Use mechanical stirrer
-Size of sample
Use vernier calipers to standardize the length at ___mm for each test
6. Estimate unknown value
If the value lies between 2 data, do not give a random value between the 2 data values. Always write betweem ___ and ___.
7. Systematic and random errors.
Systematic error is caused by flawed in measuring instruments and also other apparatus.
It affects all results in the same way and true value is hard to obtained.
Ways to improve : use the same instrument for a ll samples so that the error is consistent.
Random error is caused by human error or unpredictable change in the experiment.
It does not affect results in the same way. It affects the general trend (anomalous result)
Ways to improve : take more readings and calculate the mean
8. Significant sources of error & Suggesting improvements
Errors that affect all samples equally cannot be taken into account. Eg, syringe used, solutions degrading. Human reaction time and contamination also not allowed.
Cutting samples
-Size of samples are different.
~Use vernier caliper to measure the length of samples before cutting
Stirring
-Mixing of solutions are different
~Use a mechanical stirrer
Incubation periods
-Time of samples soaked in the incubating solutions are different
~Staggered the starting time
Colour changes
-Difficult to judge the end point
~Use a colorimeter to judge the end point colour
9. Reliability & Accuracy
To improve reliability:
-Make more replicates and calculate the mean
-Standardize variables
To improve accuracy :
-Use more intermediate of (independent variable), such as ___________________
-Standardize variables
-Plot a graph and read off the anomalous value
10. Modifying experiment
Set up (independent variable) at (at least 5 readings) + how the independent variable conditions set up
Eg.
Set up the temperature for ______ at 25°C, 30°C, 35°C, 40°C and 45°C by using a thermostatically controlled water bath.
11. Calculating errors
(1/2 x smallest division on instrument) / total x 100%
12. Plotting graph
-Label both x- and y-axis with suitable UNITS
-Use scales like factor of 2, 5 and 10. You don't have to start with 0
-Plot must be smaller than the little box of the graph paper.
-Smooth line
Be careful of bar charts and histogram. DO NOT shade them!
Bar chart do not touch each other while histogram do touch each others.
13. Drawing
Plan diagram :
-NO ruler
-DO NOT shade the drawing
-DO NOT draw any celss
-draw bigger than the diagram given
-read the questions properly and watch out for annotation
High power diagram :
-Draw cell wall as double line
-only draw what you see
14. Calculation
-Always in mm
-Show full calculation steps!
-convert to μm first for calculation before convert back to mm for final answer
-Magnification must be whole number
-Ratios must be whole number and lowest denominator
15. Comparison/ Differences
Draw a table with 3 columns : features and 2 heading of the samples
For comparison, show both similarities and differences.
For differences, show only differences.
Compare only visible features.
-shape
-distribution of structures
-presence and absence of structures
-size
-number
SPM is a very important exam. Everyone wants to strive for an excellent result so that they can get discount when studying foundation in college, get scholarships or bursaries (I don't care if they still have this) or just purely show-off?
Whatever the reasons are, SPM is still very important. So, I'm going to tell u guys some tips for the subjects that I sat SPM
The first ultimate tip is...
DO NOT leave the questions blank! The time for each paper is super long, so you don't have any excuses that you can't finish the paper. Just write anything that make sense (even though it doesn't make sense, you still have to write it). Who knows you're just lucky enough to obtain a few more marks. Right?
The second ultimate tip is...
Write as much as you can. This comes to hand in all subjects except Maths and Additional Maths. No matter how much you write, your mark will not be deducted. If you're lucky enough, maybe you can gain a few marks.
1. Bahasa Malaysia/Melayu
For the komsas/ novel section, I depended on my tuition centre. My tutor will force us to read komsas in class instead of at home because you know, we won't read it at home. If your teacher attempt to make you read it in school, just do it. It's for your own good. Know the story line, and everything is good.
As for the essay, read a lot of news. The latest news, the better. Then, try to stuff everything you know into your essay. Good Malay is a must, but honestly peribahasa is not that important. The part that you have the general knowledge is more significant.
For the tatabahasa, erm...I'll just skip this part. HAHAH
2. BI
Read your freaking novel no matter how boring it is. You still have to deal with it. Just remember the story line then ok, you're done.
For essay, read a lot of storybooks, I guess...
Oh well, language subjects are really hard to give tips, y'know...
3. Maths / Additional Maths
Do a lot of exercise. Get use to how the questions ask and where do you apply which formula. Additional Maths is the only subject that I think the time is crucial. So, if you can't do the first questions, skip it. Just do whatever you know first and come back to the questions you don't know. Don't waste to much time when you know it is useless to do so.
4. Sejarah
Use your textbooks wisely. Love your textbooks because it is important compared to reference books. Textbooks have all the things you need to memorize. Don't freaking use the shitty reference books that give extra information and make you confused and waste time and angry and stressed and...
So, how many times exactly do you have to read your textbooks before SPM? I would say two times...For the first time, read it in detail. As for the second time, just scan through la. You don't have much time to spend for this shit.
5. P. Moral
This subject is extremely annoying. I was so frustrated of this particular subjects. Why? Because they keep on changing the format!!! If they want to change format just let them be because there's an ultimate tips for Moral which is...
Watak+definisi+huraian+huraian+...+contoh+contoh+...
Yes, that's right! Just write as many huraian and contoh as you can. Squeeze your brain juice and think.
6. Physics
I hate this the most out of the three sciences. Let's get back to the point...
If I'm not wrong, a lot of definitions will be asked in the paper. So, just list out every definition in a piece of paper or small booklets or whatever you like, then start memorize it. Nevertheless, do past paper and exercises to get used of the pattern of the questions.
7. Chemistry
Same thing again, do a lot of past paper. And, DON'T FORGET to balance your freaking equation. Basically, chemistry is to test your understanding, so make sure you read your notes or reference book and understand the details fully. Make your own notes if you can since there's alot of colour solution and precipitated which is hard to memorize.
8. Biology
Once again, do your past paper!
Biology, like Sejarah is pure memorize (for SPM). I know it is hard to memorize all those terms. So, you'll have to make your own mindmap. Either you scribble it or draw it nicely on a piece of paper. Diagrams and pictures are always useful to make you remember things better.
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Those are the subjects that I sat SPM. So, how exactly do I study for it?
To be honest, I am a very lazy student, and I tend to do everything in last minute. But, I still manage to get 9As for my SPM.
SPM English is still considered okay, I bet most people have no problem with it.
However, SPM BM is really a pain in ass. I really hate studying BM, but I still gotta do this shit. I swear I depended on my tuition centre all the way because I don't study BM at home.
Maths is easy, so I don't give much attention to it.
Add maths is two times harder than Maths. I went for extra class for this subjects, so I manage to do at least one paper every week.
I think I only read the Sejarah textbooks three times during my Form 5 year. One before the semester exam, and two times before SPM. Even if I read it every single day, I'll still going to forget it. So why not last minutes?
There's a short break before my P.Moral paper. So I just take the time to swallow all the definisi.
I think I'm just lucky for Physics. Paper 1 was always hard for me. I attend tuition class for this subject too.
Chemistry is my favourite out of the 3 sciences. My Chemistry teacher was very lenient and she made the subject very interesting so I can remember and memorize very well.
I attended a Biology seminar few days before the real paper. That seminar really made me have hope in myself. They didn't give tips but instead they give a lot of notes in diagram form. I use the remaining days to swallow all the diagrams.
If you think you're more hardworking than me, then I'm sure you can scored very well in SPM.
