A hole in the heart

We always talk about conditions affecting the heart later in life such as hypertension, coronary heart disease and heart failure. We don't talk much of any conditions of the heart which are present at birth, known as congenital heart disease or defects. Congenital heart disease, also abbreviated to CHD and not to be confused with coronary heart disease, is a type of defect or malformation in one or more structures of the heart or blood vessels that occurs before birth. These defects happen as the foetus is developing. CHD is more common than one thinks, occurring around 8 to 10 out of every 1,000 births. The cause is unknown in the majority of cases although certain conditions or factors can predispose a child to being born with CHD. They include genetic or chromosomal abnormalities in the child such as Down's Syndrome, viral infections in the mother during pregnancy such Rubella, and consumption of certain drugs or alcohol by the mother during pregnancy. There are many different types of CHD and they range from a mild form that can go undetected until much later in life to the very severe where the baby is cyanosed - bluish discolouration of the lips and face because of lack of oxygen in the blood - within days of being born. Let us just limit the discussion here to atrial and ventricular septal defects, known as ASD and VSD respectively. In layman's term, they are also known as hole-in-the-heart. You all knoe that the heart is divided into four chambers - two on the left where blood rich in oxygen from the lungs passes through to get to the body - and two on the right where blood lacking in oxygen returning from the body goes to before it gets back to the lungs. It is vital that the wall separating the two sides called the septum is intact. Any breach in the wall will mean that blood with different oxygen concentrations are mixed together. ASD is when the breach is in the septum between the two atria and likewise, VSD denotes a defect in the ventricular septum. This may not be a big problem in the beginning as the left chambers which have a higher pressure system than the right will direct blood to the right chambers via the hole or defect in the wall. However, as the pressure rises in the right chambers through the years because of constant flow of high pressure from the left, it can damage the lung causing pulmonary hypertension. When it comes to a point where both sides have the same blood pressure level, there is then a free mixing of high and low oxygenated blood on both sides resulting in body tissues being compromised of good oxygenation. The person will be cyanosed and breathless and may also have symptoms of heart failure. Of course, that is the extreme end of the spectrum. For most with ASD or VSD, they are fairly asymptomatic and the condition only gets discovered during a routine medical examination when a murmur - a characteristic sound heard by using a stethoscope placed on the chest over the heart - is detected. The definitive test is an echocardiogram which is an ultrasound scan test of the heart. When the septal defect is small the doctor will usually advise the person concerned to come back for a checkup every year or so. No regular medication is needed. He will be advised to take antibiotics as a preventative measure against bacterial infection affecting the heart (endocarditis) if he is going to have a dental procedure or any procedure that may cause bleeding. If the defect is big from the echocardiogram, then an interventional procedure or surgery to close the hole has to be considered. If you are a parent and you notice the following in your child - cyanosis of the skin, lips and fingernails, poor weight gain, fast breathing, recurrent lung infections and inability to exercise well, it is suggested that you bring your child to the attention of your doctor or paediatrician. There is a possibility that he or she has a congenital heart disease.

Getting along with your teachers

Your Maths teacher wears clothes from 1982 and always mispronounces your name. Your English teacher loves to start classes with pop quizzes. It can be hard to think of these givers of grades as real people. But they eat nasi lemak, drink teh tarik, watch movies, and enjoy sports on the weekends, just like you. So how can you get along with your teachers? Here are some tips. Why Work on Good Relationships With Teachers? A good relationship with a teacher today may help you in the future. You will need teachers' written recommendations to apply to a college or for a job after school. And if you're thinking about going into a career in science, who better to ask about the field than your science teacher? Teachers are often plugged into the community and may be the first to find out about local competitions, activities, or contests. They also may know about scholarships. Teachers are another group of adults in your life who can look out for you, guide you, and provide you with an adult perspective. Many are willing to answer questions, offer advice, and help with personal problems. Developing Good Teacher-Student Relationships We all have our favourite teachers — those who seem truly interested and treat us as intelligent beings. But what about teachers we don't know as well (or even don't like much)? You can do lots of things to get a good connection going with your teacher. First, do the obvious stuff: show up for class on time, with all assignments completed. Be alert, be respectful, and ask questions. Show an interest in the subject. Obviously, your teachers are really interested in their subjects or they wouldn't have decided to teach them! Showing the teacher that you care — even if you're not a math whiz or fluent in English — sends the message that you are a dedicated student. You can also schedule a private conference during a teacher's free period. Use this time to get extra help, ask questions, inquire about a career in the subject, or talk about your progress in class. You may be surprised to learn that your teacher is a bit more relaxed one-on-one than when lecturing in front of the whole class. It is possible to try too hard, though. Here are some things to avoid when trying to establish a relationship with your teacher: Not being sincere. Teachers sense when your only motivation is to get special treatment, a college reference, or a recommendation. Trying to be teacher's pet. Your behaviour will come off as phony and your classmates may start to resent you. Giving extravagant gifts. It's OK to offer a small token of appreciation to teachers if they've been helpful to you. But flashy, expensive items could send the wrong message, and a teacher is usually not allowed to accept anything expensive. Common Teacher-Student Problems If you're having problems with a teacher, try to figure out why. Do you dislike the subject? Or do you like the subject but just can't warm up to the teacher? If you don't like the subject being taught, it can affect your relationship with the teacher. Some students say it helps them to think of classes that seem like chores as stepping stones toward a bigger goal, like getting a diploma or going on to college. That allows them to keep the class in perspective. Other students say they try to find the practical value in classes they don't like. You may hate maths, but learning how to calculate averages and percentages can help you in everything from sports to leaving a tip. If you find a subject hard, talk to your teacher or a parent about extra tutoring. If you find it boring, talk to your teacher (or another favourite teacher, friend, or parent) about ways to see the subject in a different light. Mat constantly fell asleep in his sophomore history class because the past seemed so removed from reality. But things changed when he mentioned his struggle over a project to his homeroom teacher. The teacher talked to Mat and found out that his great-grandfather had fought with the communist. The teacher suggested Mat uses his great-grandfather's letters in his project. Not only did Mat get an A, he also learned a lot about a family member he barely remembered from childhood. What if you just don't like the teacher? When it comes to working with teachers, personality can come into play just as it can in any relationship. People naturally just get along better with some people than with others — it's impossible to like everyone all the time. Learning to work with people you don't connect with easily is a good skill to have in life, no matter what your goals are. If you feel at odds with your teacher, pick your battles carefully. Questioning a grade or asking to retake a test once is fine. But second-guessing a teacher's judgment on your grades all the time may annoy him or her. Constantly squabbling over a few points on every test can cause friction in your relationship. Common courtesy and respect are basic requirements of any relationship. Just as teachers need to be fair and treat everyone equally, students have responsibilities too. You don't have to like your teacher or agree with what he or she says, but it is necessary to be polite. If you need to be out of school for medical or other reasons, let your teacher know. And it's your responsibility to make up the work from missed classes. Don't expect your teacher to hunt you down or take class time to fill you in. Just like personal problems can sometimes slow you down, the same is true for your teachers. Job stress, family issues, or health problems are all factors that can affect a teacher's performance, leaving him or her cranky, irritable, or unable to concentrate. Keep in mind that too much disciplinary action can show up on a student's permanent record. This means that when someone asks for your school record, they can see the things you did — even if they happened years ago. What to Do if You Don't Get Along Before you try to get out of a class to escape a teacher you don't like, here are a few things you can try to make a difficult relationship work: Meet with the teacher and try to communicate what you're feeling. Tell him or her what's on your mind, using statements such as, "It embarrasses me in class when I feel like my intelligence is being put down" or "I can't learn in class when I feel like only a few people ever get called on to participate." See if you can work it out between the two of you. Ask yourself, "What can I learn from this teacher?" Even if you don't worship his or her personality or lectures, dig deep until you find a subject in which your teacher is very knowledgeable. Focus on that part of the teacher's personality, and use it as a tool for learning. Not only will you gain more knowledge in that subject, but a closer relationship with your teacher may help you understand one another better. Talk to students who are doing well in the class and ask them for tips, tools, and a plan of action to get along with the teacher better. Sometimes having a second set of notes can be helpful, so asking a classmate who is willing to share them with you is a great idea. If you're too shy to talk to other students, study their actions and behaviour in the classroom and try to follow that lead. If you still can't get along, make an appointment with the school counselor, who can offer many tips and suggestions for getting more out of difficult teacher relationships. Sometimes a counselor can act as a mediator between you and the teacher. Teachers are there for more than just homework, and they know about more than just their subject matter. They can help you learn how to function as an adult and a lifelong learner. Undoubtedly, there will be a few teachers along the way who you'll always remember — and who might change your life forever.

KBAT or HOTS

Peperiksaan Pusat Amali Sains untuk subjek Physics, Chemistry, Biology dan Additional Science SPM 2015

Biology Workshop Paper 2 and Paper 3 (SM Sains Kubang Pasu)

Jaundice among newborns

Jaundice refers to the yellow colour of the skin and whites of the eyes caused by excess bilirubin in the blood. Bilirubin is produced by the normal breakdown of red blood cells.

Normally, bilirubin passes through the liver and is excreted as bile through the intestines. Jaundice occurs when bilirubin builds up faster than a newborn's liver can break it down and pass it from the body. Reasons for this include:

  Newborns make more bilirubin than adults do since they have more turnover of red blood cells. 

  A newborn baby's still-developing liver may not yet be able to remove adequate bilirubin from the blood. 

  Too large an amount of bilirubin is reabsorbed from the intestines before the baby gets rid of it in the stool. 

High levels of bilirubin — usually above 25 mg — can cause deafness, cerebral palsy, or other forms of brain damage in some babies. In less common cases, jaundice may indicate the presence of another condition, such as an infection or a thyroid problem. The American Academy of Pediatrics (AAP) recommends that all infants should be examined for jaundice within a few days of birth.

Types of Jaundice

The most common types of jaundice are:

Physiological (normal) jaundice: occurring in most newborns, this mild jaundice is due to the immaturity of the baby's liver, which leads to a slow processing of bilirubin. It generally appears at 2 to 4 days of age and disappears by 1 to 2 weeks of age.

Jaundice of prematurity: occurs frequently in premature babies since they are even less ready to excrete bilirubin effectively. Jaundice in premature babies needs to be treated at a lower bilirubin level than in full term babies in order to avoid complications.

Breastfeeding jaundice: jaundice can occur when a breastfeeding baby is not getting enough breast milk because of difficulty with breastfeeding or because the mother's milk isn’t in yet. This is not caused by a problem with the breast milk itself, but by the baby not getting enough to drink.

Breast milk jaundice: in 1% to 2% of breastfed babies, jaundice may be caused by substances produced in their mother's breast milk that can cause the bilirubin level to rise. These can prevent the excretion of bilirubin through the intestines. It starts after the first 3 to 5 days and slowly improves over 3 to 12 weeks.

Treatments

In mild or moderate levels of jaundice, by 1 to 2 weeks of age the baby will take care of the excess bilirubin on its own. For high levels of jaundice, phototherapy — treatment with a special light that helps rid the body of the bilirubin by altering it or making it easier for your baby's liver to get rid of it — may be used.

More frequent feedings of breast milk or supplementing with formula to help infants pass the bilirubin in their stools may also be recommended. In rare cases, a blood exchange may be required to give a baby fresh blood and remove the bilirubin.

If your baby develops jaundice that seems to be from breast milk, your doctor may ask you to temporarily stop breastfeeding. During this time, you can pump your breasts so you can keep producing breast milk and you can start nursing again once the condition has cleared.

If the amount of bilirubin is high, your baby may be readmitted to the hospital for treatment. Once the bilirubin level drops and the treatment is stopped, it is unlikely that treatment for jaundice will need to be restarted.

Blood group incompatibility (Rh or ABO problems): if a baby has a different blood type than the mother, the mother might produce antibodies that destroy the infant's red blood cells. This creates a sudden buildup of bilirubin in the baby's blood. Incompatibility jaundice can begin as early as the first day of life. Rh problems once caused the most severe form of jaundice, but now can be prevented with an injection of Rh immune globulin to the mother within 72 hours after delivery, which prevents her from forming antibodies that might endanger any subsequent babies.

Symptoms and Diagnosis

Jaundice usually appears around the second or third day of life. It begins at the head and progresses downward. A jaundiced baby's skin will usually appear yellow first on the face, followed by the chest and stomach, and finally, the legs. It can also cause the whites of an infant's eyes to appear yellow.

Since many babies are now released from the hospital at 1 or 2 days of life, it is best for the baby to be seen by a doctor within 1 to 2 days of leaving the hospital to check for jaundice. Parents should also keep an eye on their infants to detect jaundice.

If you notice your baby’s skin or eyes looking yellow you should contact your child's doctor to see if significant jaundice is present.

At the doctor's office, a small sample of your infant's blood can be tested to measure the bilirubin level. Some offices use a light meter to get an approximate measurement, and then if it is high, check a blood sample. The seriousness of the jaundice will vary based on how many hours old your child is and the presence of other medical conditions.

Biological Terms

One of the keys to being successful in biology is being able to understand the terminology. Difficult biology words and terms can be made easy to understand by becoming familiar with common prefixes and suffixes used in biology. These affixes, derived from Latin and Greek roots, form the basis for many difficult biology words.

Below is a list of a few biology words and terms that many biology students find difficult to understand. By breaking these words down into discrete units, even the most complex terms can be understood. 

1. Autotroph

This word can be separated as follows: Auto - troph.

Auto - means self, troph - means nourish. Autotrophs are organisms capable of self nourishment.

2. Cytokinesis

This word can be separated as follows: Cyto - kinesis.

Cyto - means cell, kinesis - means movement. Cytokinesis refers to the movement of the cytoplasm that produces distinct daughter cells during cell division.

3. Eukaryote

This word can be separated as follows: Eu - karyo - te.

Eu - means true, karyo - means nucleus. A eukaryote is an organism whose cells contain a "true" membrane bound nucleus.

4. Heterozygous

This word can be separated as follows: Hetero - zyg - ous.

Hetero - means different, zyg - means yolk or union, ous - means characterized by or full of. Heterozygous refers to a union characterized by the joining of two different alleles for a given trait.

5. Hydrophilic

This word can be separated as follows: Hydro - philic.

Hydro - refers to water, philic - means love. Hydrophilic means water-loving.

6. Oligosaccharide

This word can be separated as follows: Oligo - saccharide.

Oligo - means few or little, saccharide - means sugar. An oligosaccharide is a carbohydrate that contains a small number of component sugars.

7. Osteoblast

This word can be separated as follows: Osteo - blast.

Osteo - means bone, blast - means bud or germ (early form of an organism). An osteoblast is a cell from which bone is derived.

8. Tegmentum

This word can be separated as follows: Teg - ment - um.

Teg - means cover, ment - refers to mind or brain. The tegmentum is the bundle of fibers that cover the brain.

Pneumonoultramicroscopicsilicovolcanoconiosis

Yes, this is an actual word. What does it mean? Biology can be filled with words that sometimes seem incomprehensible. By "dissecting" these words into discrete units, even the most complex terms can be understood. To demonstrate this concept, let's begin by performing biology word dissections on the word above.

To perform our biology word dissection, we'll need to proceed carefully. First, we come to the prefix (pneu-), or (pneumo-) which means lung. Next, is ultra, meaning extreme, and microscopic, meaning small. Now we come to (silico-), which refers to silicon, and (volcano-) which refers to the mineral particles that make up a volcano. Then we have (coni-), a derivative of the Greek word konis meaning dust. Finally, we have the suffix (-osis) which means affected with. Now lets rebuild what we have dissected:

Considering the prefix (pneumo-) and the suffix (-osis), we can determine that the lungs are affected with something. But what? Breaking down the rest of the terms we get extremely small (ultramicroscopic) silicon (silico-) and volcanic (volcano-) dust (coni-) particles. Thus, pneumonoultramicroscopicsilicovolcanoconiosis is a disease of the lungs resulting from the inhalation of very fine silicate or quartz dust. That wasn't so difficult, now was it?

Now that we've honed our dissection skills, let's try some frequently used biology terms. For instance:

Arthritis

(Arth-) refers to joints and (-itis) means inflammation. Arthritis is the inflammation of a joint(s).

Erythrocyte

(Erythro-) means red and (-cyte) means cell. Erythrocytes are red blood cells.

Okay, let's move on to more difficult words. For instance:

Electroencephalogram

Dissecting, we have (electro-), pertaining to electricity, (encephal-) meaning brain, and (-gram) meaning record. Together we have an electric brain record or EEG. Thus, we have a record of brain wave activity using electrical contacts.

Schizophrenia

Individuals with this disorder suffer from delusions and hallucinations. (Schis-) means split and (phren-) means mind.

Thermoacidophiles

These are ancient bacteria that live in extremely hot and acidic environments. (Therm-) means heat, next you have (-acid), and finally (phil-) means love. Together we have heat and acid lovers.

Once you understand the commonly used prefixes and suffixes, obtuse words are a piece of cake! Now that you know how to apply the word dissection technique, I'm sure you'll be able to determine the meaning of the word thigmotropism (thigmo - tropism).

Much ado over rankings

The nation’s low rankings in a world educational assessment has caused an outcry, yet our schools have nurtured many young Malaysians who have at the global level, excelled academically. 

I REFER to recent comments made on the poor performance of Malaysian students in the Programme for International Student Assessment (Pisa).

Many seem to agree with the declining standards of the Malaysian education system.

If the “leaning indicator of Pisa” is to be accepted as the true picture, Malaysian education seems to be heading towards a calamity.

There was also talk that since Malaysians were not up to the mark, there were none who earned a spot in Harvard University in the United States.

Is failure to gain entry into Harvard the measurement of failure of education in a country? However, let us give credit where credit is due.

Malaysia has done relatively well in using her natural wealth to build her economy.

We managed to transform from a country that relied on the export of natural resources to one that exports manufactured goods.

The success of our transition can be credited to our heavy investment in education.

Education gives birth to human capital. The 25% allocation for education in the budget simply means the importance stressed by the Government on human capital.

Economists have come to believe that the central determinant of a nation’s economic growth is the skill and entrepreneurial courage of the population.

Just look at countries like Japan, Korea, Taiwan and Singa-pore. They are successful for the simple reason that they have put so much emphasis on the quality of their schools.

Comments and actions taken by the pessimists have been shocking. We see parents sending their children to international and private schools.

Well, it is their right. They have the means. Most of them flock to schools that use English as the medium of instruction.

So where does that put Malaysian schools as a start to creating human capital?

If one reads and scrutinises the criticisms on the Malaysian school education system, one will think it produces dullards of the worst kind.

The criticisms seem to show that our school system is a national disgrace.

The strings of As every year in the SPM have been branded as over inflated and not reflective of the actual academic standards of students.

If that is the case, then how is it that local students can achieve excellent results when they sit for pre-university exams conducted by foreign agencies, prior to pursuing studies at high-ranking institutions abroad?

How can this paradox be explained?

Their performance shows that the education system here is a lot better than what the critics say.

So, there must be something right in our school system that contributes significantly to human capital later on.

Simply put, the education system is not as bad as it is painted out to be.

We are a pessimistic lot. We are ever so willing to criticise despite the dynamism and sustained growth performance in many sectors shown over the years.

Compared to many countries, those in our cohort could envy us. Had our education been poor, we would not have been where we are today.

Some may say that the good performances by several sectors may be due to them being highly populated by officers who graduated from overseas’ universities.

If that is so, how did they gain entry into these universities?

The A-Levels, Edexcel, International Baccalaureate and other matriculation exams sat by governing bodies abroad are tough.

So how did our students manage to get the high grades needed in these exams to gain entry into many good universities in the United Kingdom, Canada, Australia and the United States?

Nobody questions over inflated grades simply because they are conducted by foreign agencies.

Didn’t the formative years in the primary and the secondary schools here contribute to their good performance in those exams?

If so, it shows that our education has helped the students have what it takes to gain entry to reputable colleges and universities.

Many may argue that the excellent performance of the students at the pre-university exams may be because of the good colleges they attended.

My answer is simple, those entrusted to teach at these colleges were no wizards. They could not do wonders within one or two years.

The argument could then go on to the high standards that the foreign universities they attended had maintained.

While we accept that not many were able to make it to the Ivy League, our students and many from around the world have made it to other established varsities.

What does this all mean? If our students are bad, they would not have gained entry into these institutions.

Yes, there is a decline in the standard of English among our students and graduates.

There is much to be desired in communication and social skills. Their general knowledge is very embarrassing.

These are also the type of comments made by other countries on their present generation of graduates.

Malaysia is not alone in facing the drop in the standard of education. Yes, even the British and the Americans are complaining that their students’ command of grammar of their own mother tongue is shameful. Their general knowledge is abysmal.

All these should heighten concerns about the quality of the teaching of language and subjects like history and geography, as well as the syllabuses in those subjects in their schools as well as ours and in stressing a two-way communication in classes and improvement in soft skills.

Those skills that are lacking can also be acquired as the graduates move along in organisations they work in.

The problem with organisations is that they expect graduates to be perfect from the first day that they step in as employees.

Organisations expect all shortcomings of the graduates to be overcome at the universities they attend but do not realise that universities too have their limits.

The rest is up to the graduates and the organisations to turn potentials into real human capital.

We can never be complacent about our duty to education.

All must take responsibility to ensure that what is best is passed to the next generation. Every generation is a product of its environment.

My parting shot. On several occasions (not only based on Pisa), the Americans and Western Europeans have lagged behind East Asians in academic performance in elementary education.

Somehow, several Nobel Prize winners consistently every year are Americans and Europeans.

Where are the scientists and thinkers from East Asia? The test scores such as in Pisa may not display the shape of people to come.

Dr. Azmi Yaakob

Sample STPM Semester I Question

ATP and NADPH are two main molecules which are required for the production of carbohydrate in plants. Describe how these molecules are generated during photosynthesis.

[9 marks]

P680/Photosystem II absorb light energy/photon.

Energy is passed from one pigment molecule to another pigment molecule until reach the reaction centre.

The electron is excited and captured by primary electron acceptor.

Created electron hole in P680/photosystem II.

Which filled up by electron from photolysis of water

Primary electron acceptor passes the electron to a series of electron carriers/plastoquinone, cytochrome complex and plastocyanine

Energy released in the form of ATP through chemiosmosis

P700/photosystem I absorbs light energy/photon

The electron excited and captured by primary electron acceptor

Electron is passed to ferredoxin

NADP+ is reduced to NADPH.

PMR 2014

DALAM satu program temu bual di televisyen penulis ditanya mengenai tindakan pemansuhan peperiksaan Penilaian Menengah Rendah (PMR). Seperti yang dilaporkan dalam akhbar di mana tahun ini adalah merupakan tahun terakhir pelajar Tingkatan 3 menduduki peperiksaan awam tersebut. Penulis menyatakan bahawa sebenarnya peperiksaan PMR tidak dimansuhkan. Peperiksaan itu akan diteruskan pada tahun-tahun yang akan datang. 

Walau bagaimanapun formatnya akan diubahsuai dalam bentuk yang baharu. Perubahan ini selaras dengan transformasi pendidikan iaitu untuk menjadikan kaedah pentaksiran lebih bersifat holistik dan berupaya menilai kebolehan pelajar melalui berbagai komponen.

Huraian transformasi kurikulum dan pentaksiran tersebut dapat dirujuk melalui 'Bab 4 - Pembelajaran Murid' dalam Pelan Pembangunan Pendidikan Malaysia (PPPM) 2013-2025 yang telah dilancarkan oleh Timbalan Perdana Menteri, Tan Sri Muhyiddin Yassin baru-baru ini. 

Sesungguhnya perubahan ketara peperiksaan PMR yang akan datang ialah pelaksanaannya menggunakan kaedah Pentaksiran Berasaskan Sekolah (PBS). PBS itu mempunyai dua komponen iaitu akademik dan bukan akademik. Komponen akademik terdiri daripada Pentaksiran Sekolah (PS) dan Pentaksiran Pusat (PP). Sementara itu komponen bukan akademik mengandungi Pentaksiran Psikometrik (Ppsi) dan Pentaksiran Aktiviti Jasmani, Sukan dan Kokurikulum (PSJSK).

Pentaksiran Sekolah atau PS bermaksud penyediaan soalan dan pemeriksaan jawapan akan diuruskan sendiri oleh guru di sekolah berkenaan. Kandungan soalan yang dikemukakan merangkumi pembelajaran dan pengajaran mulai Tingkatan 1 hingga Tingkatan 3.

Pentaksiran Pusat atau PP pula merupakan penilaian bertulis yang disediakan oleh Lembaga Peperiksaan Malaysia (LPM). LPM akan menyediakan tugasan, instrumen pentaksiran setara, peraturan penskoran, jadual pelaksanaan dan garis panduan. Namun demikian guru akan diberi tanggungjawab untuk mentadbir, mentaksir dan menskor jawapan pelajar berdasarkan peraturan dan panduan yang telah ditetapkan oleh LPM.

Ini bermakna mulai tahun 2014 semua mata pelajaran dalam peperiksaan PMR akan ditaksir dalam bentuk PS dan PP oleh guru-guru di sekolah berkenaan. Tiada lagi peperiksaan berpusat dilaksanakan serentak di seluruh negara yang dikendalikan sepenuhnya oleh LPM seperti yang diamalkan sebelum ini.

Apa yang menariknya peperiksaan PMR 2014 yang berwajah baru itu tidak hanya menilai pelajar melalui komponen akademik atau bidang kognitif semata-mata. Tetapi turut dinilai ialah komponen bukan akademik merangkumi bidang sahsiah, bakat dan kebolehan semula jadi pelajar melalui kaedah Ppsi dan PSJSK.

Menilai

Pentaksiran Psikometrik atau Ppsi merupakan suatu penilaian yang direkabentuk bagi mendapat maklumat pelajar secara kualitatif dan kuantitatif. Ppsi menilai keupayaan seseorang untuk bertindak balas dalam suatu cara tertentu. Ia juga mengukur kebolehan semula jadi atau innate ability dan kebolehan yang diperolehi atau acquired ability daripada pengalaman dan persekitaran. 

Di samping itu Ppsi juga turut menilai bakat pelajar dalam bidang muzik, kreativiti, kemahiran interpersonal dan intrapersonal, kinestatik dan kepintaran naturalis. Pentaksiran ini disediakan dalam bentuk deskriptif mengikut keperluan sama ada secara manual atau berkomputer oleh guru dan pelajar itu sendiri.

Sementara itu, Pentaksiran Aktiviti Sukan, Jasmani dan Kokurikulum atau PSJSK adalah untuk mengukur kecergasan dan kesihatan pelajar dalam pelbagai aktiviti jasmani. Turut ditaksir penyertaan, penglibatan dan prestasi pelajar dalam pelbagai aktiviti kokurikulum dan ekstra kokurikulum. Instrumen dan panduan pentaksiran disediakan oleh LPM dan organisasi berkaitan berdasarkan bidang kepakaran masing-masing.

Ternyata peperiksaan PMR 2014 yang berwajah baru itu merupakan satu langkah kehadapan yang diambil oleh Kementerian Pendidikan sesuai dengan masa dan keadaan. Pada pendapat penulis sekurang-kurang terdapat tiga faktor yang membawa kepada perubahan tersebut.

Pertama ialah hasil daripada transformasi pendidikan menerusi perancangan strategik Pelan Pembangunan Pendidikan Malaysia. Mereka mendapati peperiksaan awam yang dilaksanakan tidak menguji kesemua kemahiran yang dihasratkan dalam sistem pendidikan kita. PPPM menganjurkan agar diambil langkah bagi meningkatkan kerangka pentaksiran dan menggunakan rujukan standard seperti yang terdapat dalam PBS. Format pentaksiran baharu ini membolehkan pelajar dinilai berdasarkan keberhasilan yang lebih luas dan dalam tempoh jangka masa lebih panjang. 

Kedua, kerap kali dikatakan bahawa pendidikan kita terlalu berorientasikan peperiksaan. Kita masih lagi mengamalkan peperiksaan awam berpusat dan dijalankan serentak di seluruh negara. Kebiasaannya penilaian terhadap pelajar tertumpu sepenuhnya kepada peperiksaan di akhir setiap peringkat persekolahan mereka. Sudah sampai masanya pentaksiran dilakukan dalam tempoh masa yang panjang dan turut menilai kebolehan pelajar di luar bidang akademik. Oleh itu semestinya komponen sahsiah, bakat, kebolehan semulajadi dan kokurikulum perlu diberi ruang dan peluang untuk dinilai.

Ketiga mengembalikan semula peranan mentaksir pelajar kepada guru. Ketika ini tugas pengajaran dan pembelajaran dilaksanakan sepenuhnya oleh guru tetapi tugas menilai pelajar diserahkan pula kepada pihak yang lain. Sekiranya peranan mentaksir pelajar diberikan sepenuhnya kepada guru maka ia dilihat lebih memberi keadilan dan kesaksamaan kepada pelajar yang terdiri daripada berbagai tahap kebolehan dan kepintaran.

Pada hakikatnya, isu guru dikatakan mengajar hanya bagi tujuan mendapat keputusan cemerlang dalam peperiksaan sering menjadi polemik. Akibatnya ada yang mengemukakan soalan sama ada peperiksaan awam patut dikekalkan atau dimansuhkan. Seharusnya apa sahaja peperiksaan tidak memberi impak negatif kepada pelajar. Namun demikian cabarannya ialah bagaimanakah peperiksaan awam yang dilaksanakan dapat menguji kesemua kemahiran seperti yang dihasratkan dalam sistem pendidikan kita.

Justeru dengan pengenalan kaedah penilaian yang berwajah baru melalui peperiksaan PMR 2014 diharapkan akan menjadi perintis kepada pentaksiran dalam peperiksaan awam yang lain di masa hadapan.

© Utusan Melayu (M) Bhd

Sample SPM Biology essay question

Diagram 6.1 shows the part of the regulatory mechanism of oxygen and carbon dioxide contents in the body.

Based on the diagram, explain how the concentration of carbon dioxide in the blood is regulated during a vigorous activity.

[8 marks]

Sample answer

During vigorous activity, the concentration / the partial pressure of carbon dioxide increases as a result of active cellular respiration

Carbon dioxide reacts with water to form carbonic acid which results in a drop in the pH level of the blood and tissue fluid that bathing the brain

The drop in pH is detected by the central chemoreceptors in the medulla oblongata

and also detected by the peripheral chemoreceptors (carotid bodies and aortic bodies)

The central chemoreceptors and pheripheral receptors send nerve impulses to the respiratory centre in the medulla oblongata

The respiratory centre sends nerve impulses to the diaphragm and the intercostal muscles, causing the respiratory muscle to contract and relax faster

As a result, the breathing rate and ventilation rate increase causes more oxygen inhaled and the oxygen concentration return to the normal level

As excess carbon dioxide is eliminated from the body, the carbon dioxide concentration and pH value of the blood return to normal level.

ii) Explain why the pulse rate takes several minutes to return to normal after a vigorous activity.

[4 marks]

Sample answer

After vigorous activity, the pulse rate takes several minutes to return to normal because during the activity the oxygen intake is not able to meet the oxygen demand of the body.

Respiration has to take place anaerobically/anaerobic respiration occurs

As a result, lactic acid accumulates in the muscle.

So more oxygen is needed to oxidise the lactic acid and to provide the energy for the recovery of the muscle

The Lymphatic System

Closely connected with the blood and circulatory system, the lymphatic system is an extensive drainage system that returns water and proteins from various tissues back to the bloodstream. It is comprised of a network of ducts, called lymph vessels and carries lymph, a clear, watery fluid that resembles the plasma of blood. Some scientists consider this system to be part of the blood and circulatory system because lymph comes from blood and returns to blood, and because its vessels are very similar to the veins and capillaries of the blood system. Throughout the body, wherever there are blood vessels, there are lymph vessels, and the two systems work together.

How Are the Spleen and Lymphatic System Necessary for Living?

The entire lymphatic system flows toward the bloodstream, returning fluid from body tissues to the blood. If there were no way for excess fluid to return to the blood, our body tissues would become swollen. For example, when a body part swells, it may be because there is too much fluid in the tissues in that area. The lymph vessels collect that excess fluid and carry it to the veins through the lymphatic system.

This process is crucial because water, proteins, and other molecules continuously leak out of tiny blood capillaries into the surrounding body tissues. This lymph fluid has to be drained, and so it returns to the blood via the lymphatic vessels. These vessels also prevent the back flow of lymph fluid into the tissues.

The lymphatic system also helps defend the body against invasion by disease-causing agents such as viruses, bacteria, or fungi. Harmful foreign materials are filtered out by small masses of tissue called lymph nodes that lie along the network of lymphatic vessels. These nodes house lymphocytes (white blood cells), some of which produce antibodies, special proteins that fight off infection. They also stop infections from spreading through the body by trapping disease-causing germs and destroying them.

The spleen also plays an important part in a person's immune system and helps the body fight infection. Like the lymph nodes, the spleen contains antibody-producing lymphocytes. These antibodies weaken or kill bacteria, viruses, and other organisms that cause infection. Also, if the blood passing through the spleen carries damaged cells, white blood cells called macrophages in the spleen will destroy them and clear them from the bloodstream.

Basic Anatomy

The lymphatic system is a network of very fine vessels or tubes called lymphatics that drain lymph from all over the body. Lymph is composed of water, protein molecules, salts, glucose, urea, lymphocytes, and other substances.

Lymphatics are found in every part of the body except the central nervous system. The major parts of the system are the bone marrow, spleen, thymus gland, lymph nodes, and the tonsils. Other organs, including the heart, lungs, intestines, liver, and skin also contain lymphatic tissue.

Lymph nodes are round or kidney-shaped, and range in size from very tiny to 1 inch in diameter. They are usually found in groups in different places throughout the body, including the neck, armpit, chest, abdomen, pelvis, and groin. About two thirds of all lymph nodes and lymphatic tissue are within or near the gastrointestinal tract.

Lymphocytes are white blood cells in the lymph nodes that help the body fight infection by producing antibodies that destroy foreign matter such as bacteria or viruses. Two types are T-cells and B-cells. Some lymphocytes become stimulated and enlarged when they encounter foreign substances; these are called immunoblasts.

The major lymphatic vessel is the thoracic duct, which begins near the lower part of the spine and collects lymph from the lower limbs, pelvis, abdomen, and lower chest. It runs up through the chest and empties into the blood through a large vein near the left side of the neck. The right lymphatic duct collects lymph from the right side of the neck, chest, and arm, and empties into a large vein near the right side of the neck.

The spleen is found on the left side of the abdomen. Unlike other lymphoid tissue, red blood cells flow through it. It helps control the amount of blood and blood cells that circulate through the body and helps destroy damaged cells.

Normal Physiology

Lymph drains into open-ended, one-way lymph capillaries. It moves more slowly than blood, pushed along mainly by a person's breathing and contractions of the skeletal muscles. The walls of blood capillaries are very thin, and they have many tiny openings to allow gases, water, and chemicals to pass through to nourish cells and to take away waste products. Interstitial fluid passes out of these openings to bathe the body tissues.

Lymph vessels recycle the interstitial fluid and return it to the bloodstream in the circulatory system. They collect the fluid and carry it from all of the body's tissues and then empty it into large veins in the upper chest, near the neck.

Lymph nodes are made of a mesh like network of tissue. Lymph enters the lymph node and works its way through passages called sinuses. The nodes contain macrophages, phagocytic cells that engulf (phagocytize) and destroy bacteria, dead tissue, and other foreign matter, removing them from the bloodstream. After these substances have been filtered out, the lymph then leaves the nodes and returns to the veins, where it reenters the bloodstream.

When a person has an infection, germs collect in great numbers in the lymph nodes. If the throat is infected, for example, the lymph nodes of the neck may swell. Sometimes the phagocytic cells may not be able to destroy all of the germs, and a local infection in the nodes may result.

Because the lymphatic system extends to the far reaches of the body, it also plays a role in the spread of cancer. This is why lymph nodes near a cancerous growth are usually removed with the growth.

Diseases, Conditions, Disorders, and Dysfunction's

Because the lymphatic system branches through most of the parts of the body, it may be involved in a wide range of conditions. Diseases may affect the lymph nodes, the spleen, or the collections of lymphoid tissue that occur in certain areas of the body.

Disorders of the lymph nodes

Lymphadenopathy. Most lymph nodes in the body can't be felt easily unless they become swollen or enlarged. Lymphadenopathy is an increase in the size of a lymph node or nodes, most often as the result of a nearby infection (for example, lymphadenopathy in the neck might be the result of an infection of the throat). Less commonly (particularly in children), swelling of the lymph nodes can be due to an infiltration of cancerous cells. If lymphadenopathy is generalized (meaning that the swelling is present in several lymph node groups throughout the body), it usually indicates that the person has a systemic disease.

Lymphadenitis, or adenitis, is an inflammation (swelling, tenderness, and sometimes redness and warmth of the overlying skin) of the lymph node due to an infection of the tissue in the node itself. In children, this condition most commonly involves the lymph nodes of the neck.

Lymphomas. A group of cancers that arise from the lymph nodes, these diseases result when lymphocytes undergo changes and start to multiply out of control. The involved lymph nodes enlarge, and the cancer cells crowd out healthy cells and may form tumors (solid growths) in other parts of the body.

Disorders of the spleen

Splenomegaly (enlarged spleen). In children, the spleen is usually small enough that it can't be felt by pressing on the abdomen, but the spleen can enlarge to several times its normal size with certain diseases. There are many possible reasons for this including various blood diseases and cancers, but the most common cause in children is infection (particularly viral infections). Infectious mononucleosis, a condition usually caused by the Epstein-Barr virus (EBV), is one of many viral infections associated with an enlarged spleen. Children and teens with an enlarged spleen should avoid contact sports because they can have a life-threatening loss of blood if their spleen is ruptured.

Disorders of other lymphoid tissue

Tonsillitis. An extremely common condition, particularly in children, tonsillitis occurs when the tonsils, the collections of lymphoid tissue in the back of the mouth at the top of the throat, are involved in a bacterial or viral infection that causes them to become swollen and inflamed. The tonsils normally help to filter out bacteria and other microorganisms to aid the body in fighting infection. Symptoms include sore throat, high fever, and difficulty swallowing. The infection may also spread to the throat and surrounding areas, causing pain and inflammation (pharyngitis).

Glossary

antibodies:

chemicals produced by white blood cells to fight bacteria, viruses, and other foreign substances

immunoblasts:

Lymphocytes that become stimulated and enlarged when they encounter foreign substances

interstitial fluid:

fluid that leaks out of capillaries (the tiniest blood vessels) and bathes body tissues

lymph vessels:

channels or ducts that contain and convey lymph; also called lymphatics

lymph:

pale fluid that bathes the body tissues, passes into lymphatic vessels, and is discharged into the blood by way of the thoracic duct; it consists of a liquid resembling blood plasma and contains white blood cells

lymph nodes:

organized masses of lymphoid tissue that are distributed along the branching system of lymphatic vessels; they contain numerous lymphocytes and other cells that filter bacteria, dead tissue, and foreign matter from the lymph that flows through them

lymphocytes:

white blood cells

macrophages:

white blood cells that remove damaged cells from the bloodstream

spleen: 

organ found on the left side of the abdomen; it helps control the amount of blood and blood cells that circulate through the body and helps destroy damaged cells

thoracic duct:

major lymphatic vessel, which begins near the lower part of the spine and collects lymph from the lower limbs, pelvis, abdomen, and lower chest; lymph flowing through the duct eventually empties into a large vein in the upper chest and returns to the bloodstream.

Digestion, Absorption and Assimilation in human (SPM level)

Digestion

Mouth

Salivary glands produce saliva which contains salivary amylase. Starch is hydrolysed into maltose.

Stomach

Gastric glands produce gastric juice which contains enzyme pepsin and rennin. Proteins are hydrolysed into polypeptide. Caseinogens is converted into casein.

Duodenum

Liver produces bile. Bile emulsifies lipid. Pancreas produces pancreatic amylase, trypsin & lipase. Starch is hydrolysed into maltose. Polypeptide is hydrolysed into peptide. Lipid is hydrolysed into fatty acids & glycerol.

Ileum

Intestinal gland secretes intestinal juice which contains enzyme maltase, lactase, sucrase and erepsin. Maltase hydrolyses maltose into glucose & glucose. Lactase hydrolyses lactose into glucose and galactose. Sucrase hydrolyses sucrose into glucose & fructose. Erepsin hydrolyses peptide into amino acids

Absorption

Glucose, amino acids, Vitamins B & C are absorbed through facilitated diffusion into blood capillaries in the villi then into hepatic portal vein that leads to liver.

Fatty acids, glycerols, Vitamin ADEK are absorbed into lacteals (FA & G in the form of lipid droplets). Then lacteal converges into lymphatic system. Flows into right lymphatic duct & thoracic duct, finally enters subclavian veins into bloodstream.

Assimilation

In the liver

Liver synthesises plasma proteins from amino acids. Short supply of glucose – liver converts amino acids into glucose. Excess amino acids are broken down – deamination. Urea is produced & transported to kidney to be excreted.

Glucose is converted & stored in the liver. Blood sugar level falls, glycogen is converted back into glucose. Liver full of glucose – converted into lipids.

Lipids enter the heart through subclavian vein transported in the bloodstream to body cells.

In the cells

Amino acids – used for synthesising new protoplasm & repair damaged tissues. Build enzymes & hormones. Synthesise plasma membrane.

Glucose – oxidised to release energy (cellular respiration). Used for muscle contraction, synthesis of proteins. Excess glucose is stored in muscles (glycogen).

Lipids – phospholipids & cholesterol : components of plasma membrane

Fats are stored around organs act as cushions that protect organs from injuries. Excess fats are stored in adipose tissue as reserve energy. When body lacks glucose, fats are oxidised to release energy.

Biology Workshop (SMK Sultanah Asma)

Nitrogen cycle

Atmospheric nitrogen cannot be absorbed directly by plants (to make proteins). 

Plants absorb nitrogen from the soil in the form of ammonium, nitrites or nitrates ions.  The process of converting atmospheric nitrogen into ammonium compounds is called nitrogen fixation.   

Nitrogen fixation is carried out by nitrogen – fixing bacteria : 

i) Nostoc sp. (cyanobacteria) &  Azotobacter sp. that live freely in soil 

ii) Rhizobium sp. that live in root nodule of leguminous plants. 

Both use atmospheric nitrogen to make ammonium compounds –(NH₃ – ammonia &  NH₄⁺ - ammonium) 

Nitrifying bacteria convert ammonium compounds into nitrites & nitrates.

The process is called nitrification.

i) Ammonia is oxidised into nitrites (NO₂^-) by Nitrobacter sp.

ii) Nitrites are oxidised into nitrates (NO₃^-) by Nitrosomonas sp.

Nitrates in the soil are absorbed by plants & converted into plant proteins.

When animals eat plants, the proteins are transferred into the body of the animals &  become animal protein. 

Dead plants, animals & waste materials are decomposed by decaying bacteria &  fungi/decomposers into ammonium compounds.

The cycle is balanced by returning of nitrogen to the atmosphere by denitrifying bacteria.

The process is called denitrification.

Denitrifying bacteria break down nitrates into gaseous nitrogen & oxygen.

Oxygen – used by bacteria; nitrogen – returned to the atmosphere.