Let's try the Trial Questions from `The land below the Wind'....
Sep 29, 2009
Let's try the Trial Questions from `The land below the Wind'....
Posted by rozaini at 11:34 PM
Here are the Johor Trial questions for P1, P2 and P3.
Posted by rozaini at 11:29 PM
• All life requires nitrogen-compounds, e.g., proteins and nucleic acids.
• Air, which is 78% nitrogen gas (N2), is the major reservoir of nitrogen.
• But most organisms cannot use nitrogen in this form.
- nitrate ions (NO3−)
- ammonia (NH3)
- Animals secure their nitrogen (and all other) compounds from plants (or animals that have fed on plants).
- nitrogen fixation
The nitrogen molecule (N2) is quite inert. To break it apart so that its atoms can combine with other atoms requires the input of substantial amounts of energy.
Three processes are responsible for most of the nitrogen fixation in the biosphere:
- atmospheric fixation by lightning
- biological fixation by certain microbes — alone or in a symbiotic relationship with some plants and animals
- industrial fixation
The enormous energy of lightning breaks nitrogen molecules and enables their atoms to combine with oxygen in the air forming nitrogen oxides. These dissolve in rain, forming nitrates that are carried to the earth. Atmospheric nitrogen fixation probably contributes some 5– 8% of the total nitrogen fixed.
Under great pressure, at a temperature of 600°C, and with the use of a catalyst, atmospheric nitrogen and hydrogen (usually derived from natural gas or petroleum) can be combined to form ammonia (NH3). Ammonia can be used directly as fertiliser, but most of it is further processed to urea and ammonium nitrate (NH4NO3).
The ability to fix nitrogen is found only in certain bacteria and archaea.
- Some live in a symbiotic relationship with plants of the legume family (e.g., soybeans, alfalfa).
- Some establish symbiotic relationships with plants other than legumes (e.g., alders).
- Some establish symbiotic relationships with animals, e.g., termites and "shipworms" (wood-eating bivalves).
- Some nitrogen-fixing bacteria live free in the soil.
- Nitrogen-fixing cyanobacteria are essential to maintaining the fertility of semi-aquatic environments like rice paddies.
Although the first stable product of the process is ammonia, this is quickly incorporated into protein and other organic nitrogen compounds.
The proteins made by plants enter and pass through food webs just as carbohydrates do. At each trophic level, their metabolism produces organic nitrogen compounds that return to the environment, chiefly in excretions. The final beneficiaries of these materials are microorganisms of decay. They break down the molecules in excretions and dead organisms into ammonia.
Ammonia can be taken up directly by plants — usually through their roots. However, most of the ammonia produced by decay is converted into nitrates. This is accomplished in two steps:
- Bacteria of the genus Nitrosomonas oxidise NH3 to nitrites (NO2−).
- Bacteria of the genus Nitrobacter oxidise the nitrites to nitrates (NO3−).
Both soil and the ocean contain archaeal microbes, assigned to the Crenarchaeota, that convert ammonia to nitrites. They are more abundant than the nitrifying bacteria and may turn out to play an important role in the nitrogen cycle.
Many legumes, in addition to fixing atmospheric nitrogen, also perform nitrification — converting some of their organic nitrogen to nitrites and nitrates. These reach the soil when they shed their leaves.
The three processes above remove nitrogen from the atmosphere and pass it through ecosystems.
Denitrification reduces nitrates to nitrogen gas, thus replenishing the atmosphere.
Once again, bacteria are the agents. They live deep in soil and in aquatic sediments where conditions are anaerobic. They use nitrates as an alternative to oxygen for the final electron acceptor in their respiration.
Thus they close the nitrogen cycle.
Are the denitrifiers keeping up?
Agriculture may now be responsible for one-half of the nitrogen fixation on earth through
- the use of fertilisers produced by industrial fixation
- the growing of legumes like soybeans and alfalfa.
Are the denitrifiers keeping up the nitrogen cycle in balance? Probably not. Certainly, there are examples of nitrogen enrichment in ecosystems. One troubling example: the "blooms" of algae in lakes and rivers as nitrogen fertilisers leach from the soil of adjacent farms (and lawns). The accumulation of dissolved nutrients in a body of water is called eutrophication.
Posted by rozaini at 10:47 PM
Sep 28, 2009
Posted by rozaini at 12:00 AM
Sep 27, 2009
Posted by rozaini at 11:52 PM
Here are some notes on photosynthesis, digestion in ruminant and rodent
Posted by rozaini at 11:46 PM
Sep 25, 2009
Tribolium confusum and Tribolium castaneum
The red flour beetle is of Indo-Australian origin and is found in temperate areas, but will survive the winter in protected places, especially where there is central heat. In the United States, it is found primarily in the southern states. The confused flour beetle, originally of African origin, has a different distribution in that it occurs worldwide in cooler climates. In the United States it is more abundant in the northern states.
Although small beetles, about 1/4 of an inch long, the adults are long-lived and may live for more than three years.
The red flour beetle is reddish-brown in colour and its antennae end in a three-segmented club. Whereas the confused flour beetle is the same colour but its antennae end is gradually club-like, the "club" consisting of four segments.
The red and confused flour beetles live in the same environment and compete for resources. The red flour beetle may fly, especially before a storm, but the confused flour beetle does not fly. Eggs, larvae, and pupae from both species are very similar and are found in similar environments. The eggs are white, microscopic and often have bits of flour stuck to their surface. The slender larvae are creamy yellow to light brown in colour. They have two dark pointed projections on the last body segment.
These beetles can breed throughout the year in warm areas. The life cycle takes from 40 to 90 days, and the adult can live for three years. All forms of the life cycle may be found in infested grain products at the same time
The red and confused flour beetles may be present in large numbers in infested grain, but are unable to attack sound or undamaged grain. The adults are attracted to light, but will go towards cover when disturbed. Typically, these beetles can be found not only inside infested grain products, but in cracks and crevices where grain may have spilled. They are attracted to grain with high moisture content and can cause a grey tint to the grain they are infesting. The beetles give off a displeasing odour, and their presence encourages mould growth in grain.
Keep in mind that these beetles may infest areas other than the pantry. Be sure to inspect spices, pet food, and flower arrangements. Also keep in mind that some stuffing in furniture or stuffed animals may have natural products that these beetles could feed on. Also be aware of areas in which any of these products may have spilled, like under the refrigerator or stove. These beetles are able to locate very small bits of food. Once all of the infested material has been removed, be sure to vacuum and clean up the area around the infestation. If you have shelf paper, it would be wise to remove it, thoroughly clean under it with soap and hot water, and replace it with new paper. Be sure to pay close attention to the cracks and crevices of any cabinets. To prevent re-infestation, all grain products should be stored in containers with tight fitting lids, or stored in the freezer. Also consider where the infestation came from. It is likely that you could have a re-infestation by purchasing infested grain products from the same business. When shopping, look for those "leaky packages". If you suspect a beetle infestation, don't buy the product.
Posted by rozaini at 12:41 PM
Two players from the top 10s, Nikolay Davdenko (Russia, ranked world 8th) and Fernando Verdasco (Spain, 10th); while five players are from the top 20s, Robin Soderling (Sweden, 11th), Fernando Gonzalez (Chile, 12th), Gael Monfils (France, 13th), Tomas Berdych (Czech Republic, 18th) and David Ferrer (Spain, 19th).
The rest are Dmitry Tursunov (Russia, 32th), Feliciano Lopez (Spain, 36th), Richard Gasquet (France, 38th), Lleyton Hewitt (Australia, 42th), Igor Kunitsyn (Russia, 43th), Martin Vassallo Arguello (Argentina, 49th), Kristof Vliegen (Belgium, 50th), Jose Acasuso (Argentina, 51st), Florent Serra (France,56th), Andrey Golubev (Kazahakstan, 57rd),Christophe Rochus (Belgium, 60th) and Mihail Youzhny (Russia, 64th).
The qualifying draw will have 32 places with three places reserved for wild cards holders, two of which will be allocated to Malaysian-based players to be chosen by the Lawn Tennis Association of Malaysia.
The Malaysian Open offers a total prize money of USD947,750 or RM3.31 million.
Posted by rozaini at 12:22 PM
Sep 19, 2009
Focus 100% on only 1 thing at any given time.
Concentrate fully on that task for that time. DO NOT allow anything to distract you, and that means NO sms, NO phone calls, NO chatting.
Let’s say you decide to learn Chap 6 of Form 4 Biology – Nutrition for the next 1 hour. Then commit to Focus 100% on that for 1 hour.
Most people (and that includes adults too) live through distractions the whole day. The world is getting more and more ADD, probably due to more and more distractions in our lives. Therefore, many people do not realise the POWER and EFFECTIVENESS of focusing 100% on something, even though it’s only for a short period of time.
Use Time Budgeting Technique.
Budget a time for your lesson. Let’s take the example of learning Chap 6 of Form 4 Biology – Nutrition. Let’s say you decide to allocate 2 hours to complete the chapter, then stick to the 2 hours. Meaning you don’t give yourself excuses and do something else in that 2 hours. (toilet break is acceptable)
It doesn’t matter whether the time allocated is enough or not. What matters is you learn the habit of FOCUSING 100% on a given task. I guarantee after FOCUSING 100% for 2 hours, you’ll definitely see significant improvement of understanding in that Chapter.
Please stop after 2 hours. Don’t over shoot your budgeted time. Learn to be disciplined.
You can be flexible – but please understand that if you’re always flexible with your time, you’ll not have enough time to finish your syllabus. Learn to balance flexibility with discipline.
Chunk Down your lessons.
Slice your budgeted 2 hours into smaller lessons. Preferably complete the lessons within a day or 2. Maximum 3 days if the chapter is long.
For example – you may decide to study 1 hour each lesson. You can study 1 hour in the morning, 1 hour in the evening and then another hour the next morning. (Remember to give 100% FOCUS to the subject matter in that 1 hour)
Create a study environment that you like.
If you like music, then study with music. If you like to munch snacks, then study with snacks. If you like cold, then study with the air-cond blasting. (BUT – please make sure you’re giving 100% FOCUS to your lessons and not your snacks!)
Try it out – You’ll be amazed with the Power of 100% Focus..
Posted by rozaini at 11:28 PM
Sep 18, 2009
There are some errors in P1, P2 questions and the answers.
Refer to your teachers for edition.
Posted by rozaini at 11:30 PM
Sep 17, 2009
“Selamat Hari Raya Aidil Fitri, Maaf Zahir dan Batin”
Posted by rozaini at 12:51 AM
Sep 15, 2009
The 6ft 6in Argentinian bludgeoned his way into the elite of the men's game by coming back to down the world No 1 with a performance that was both brilliant and courageous.
Posted by rozaini at 11:43 PM
Wanna know more about digestive system? Check this out.
Posted by rozaini at 11:20 PM
Some info on viruses and bacteria
Posted by rozaini at 10:56 PM
Posted by rozaini at 10:42 PM
Sep 13, 2009
Here are 4 modules which are quite comprehensive and effective revision for all Biology students.
Thanks a lot to the SBP teachers who have put their effort in preparing these modules.
Posted by rozaini at 12:57 PM
Sep 10, 2009
Posted by rozaini at 1:27 AM
Posted by rozaini at 1:19 AM
Sep 9, 2009
Posted by rozaini at 3:57 PM
Posted by rozaini at 3:30 PM
Posted by rozaini at 1:14 AM
Sep 8, 2009
The flow of a biology book is not like the flow of a novel. A novel can be read effortlessly, smoothly and rapidly, but biology books cannot. If you are reading a novel and are somewhat distracted, you can still get the idea of what it is about. When you are not concentrating on biology you will get very little out of it, and it will seem more difficult than it really is.
Posted by rozaini at 12:40 AM
Posted by rozaini at 12:24 AM
Sep 5, 2009
Sep 4, 2009
Posted by rozaini at 12:39 AM
Sep 1, 2009
Ensure Your Words Are Always Understood
Think of the last really memorable talk or presentation that you attended. Now, was that easy to do, or did you really have to rack your brains to remember one? Sadly, too many presentations are easy to forget. And that's a big problem because the only reason the presenter gave the talk was to communicate something to you!
However, there are three basic things that you can do to ensure that your verbal messages are understood – and remembered – time and time again.
Although somewhat obvious and deceptively simple, these are:
• Understand the purpose of the presentation
• Keep the message clear and concise
• Be prepared
• Be vivid when delivering the message
Understand what you want to achieve
Before you start working on your talk or presentation, it's vital that you really understand what you want to say, who you want to tell and why they might want to hear it. To do this, ask yourself: Who? What? How? When? Where? Why?
Who are you speaking to? What are their interests, presuppositions and values? What do they share in common with others; how are they unique?
What do you wish to communicate? One way of answering this question is to ask yourself about the ‘success criteria’. How do you know if and when you have successfully communicated what you have in mind?
How can you best convey your message? Language is important here, as are the nonverbal cues discussed earlier. Choose your words and your nonverbal cues with your audience in mind. Plan a beginning, middle and end. If time and place allow, consider and prepare audio-visual aids.
When? Timing is important here. Develop a sense of timing, so that your contributions are seen and heard as relevant to the issue or matter at hand. There is a time to speak and a time to be silent. ‘It’s better to be silent than sing a bad tune.’
Where? What is the physical context of the communication in mind? You may have time to visit the room, for example, and rearrange the furniture. Check for availability and visibility if you are using audio or visual aids.
Why? In order to convert hearers into listeners, you need to know why they should listen to you – and tell them if necessary. What disposes them to listen? That implies that you know yourself why you are seeking to communicate – the value or worth or interest of what you are going to say.
Keep it simple
When it comes to wording your message, less is more. You're giving your audience headlines. They don't need to and are usually not expecting to become experts on the subject as a result of hearing your talk.
If you're using slides, limit the content of each one to a few bullet points, or one statement or a very simple diagram
Preparation is underrated. In fact, it is one of the most important factors in determining your communication successes. When possible, set meeting times and speaking and presentation times well in advance, thus allowing yourself the time you need to prepare your communications, mindful of the entire communication process (source, encoding, channel, decoding, receiver, feedback and context). By paying close attention to each of these stages and preparing accordingly, you ensure your communications will be more effective and better understood.
Of course, not all communications can be scheduled. In this case, preparation may mean having a good, thorough understanding of the office goings-on, enabling you to communicate with the knowledge you need to be effective, both through verbal and written communications.
Your delivery of your speech or presentation will make or break it, no matter how well you've prepared and crafted your clear, concise message. Some useful tips for keeping your presentation vivid include:
• Use examples to bring your points to life
• Keep your body language up-beat – don't stay stuck behind a rostrum
• Don't talk to fast. Less is more here too. Pauses are effective.
• Use a variety of tones of voice
• Use visual aids.
Posted by rozaini at 10:34 PM
Posted by rozaini at 10:21 PM
Posted by rozaini at 10:11 PM
Posted by rozaini at 10:05 PM