December 31, 2009

For all BIOLOGY students


Biology exams can seem intimidating and overwhelming to biology students. The key to overcoming these obstacles is preparation. By learning how to study for biology exams you can conquer your fears.
Remember, the purpose of an exam is for you to demonstrate that you understand the concepts and information that have been taught. Below are some excellent tips to help you learn how to study for biology exams.

Here's How:

Get Organised
An important key for success in biology is organization. Good time management skills will help you to become more organized and waste less time preparing to study.
Items such as daily planners and semester calendars will help you to know what you need to do and when you need to have it done.

Start Studying Early
It is very important that you start preparing for biology exams well in advance.
I know, I know, it is almost tradition for some to wait until the last minute, but students who implore this tactic don't perform their best, don't retain the information, and get worn out.

Review Notes
Be sure that you review your notes before the exam. You should start reviewing your notes on a daily basis. This will ensure that you gradually learn the information over time and don't have to cram.

Review the Biology Text
Your biology textbook/reference book is a wonderful source for finding illustrations and diagrams that will help you visualise the concepts you are learning. Be sure to reread and review the appropriate chapters and information in your textbook. You will want to make sure that you understand all key concepts and topics.

Get Answers To Your Questions
If you are having difficulty understanding a topic or have unanswered questions, discuss them with your teacher.
You don't want to go into an exam with gaps in your knowledge.

Quiz Yourself
To help prepare yourself for the exam and find out how much you know, give yourself a quiz. You can do this by using prepared flash cards or taking a sample test.
You can also use online biology games and quiz resources.

Find a Study Buddy
Get together with a friend or classmate and have a study session. Take turns asking and answering questions. Write your answers down in complete sentences to help you organise and express your thoughts.

Attend a Review Session
If your teacher holds a review session, be sure to attend. This will help to identify specific topics that will be covered, as well as fill in any gaps in knowledge. Help sessions are also an ideal place to get answers to your questions.

Now that you have followed the previous steps, it's time to rest and relax. You should be well prepared for your biology exam.
It's a good idea to make sure you get plenty of sleep the night before your exam. You have nothing to worry about because you are well prepared.


QUESTION 1 (33 marks)

Record the reading of thermometer, stopwatch, measuring tools, ruler etc. from the given diagram.

State two observations….
Write down what can be observed only. Do not do the analysis, comparison or conclusion. Make sure your answer is specific.
At pH 9 the time taken for lime water to turn cloudy is 27 minutes. 
At pH 7 the time taken for lime water to turn cloudy is 1 minute.

INFERENCE (3 marks)
State one inference which corresponds to each observation.
In alkaline condition yeast activity decreases thus less carbon dioxide is released.
In neutral condition yeast activity increases compare to other conditions thus more carbon dioxide is released.

VARIABLES (3 marks)
Normally the MV and the RV can be found in the aim of the experiment.
State the 3 variables and the method to handle the variables.
(MUST USE VERB and state the INSTRUMENT used)
RESPONDING - Eg: Count and record the growth of thePleurococcus sp. in the graph paper. (SPM 2008)
CONTROLLED - Use the same…/ Maintain …/Fix

Able to state the hypothesis correctly based on the following criteria:
 State the manipulated variable
 State the responding variable
 Relate the manipulated variable and the responding variable + explanation
Eg :
When the Pleurococcus sp. faces east, it receives more sunlight therefore the total surface area covered increases. (SPM 2008)

Able to construct a table and fill a table with all columns labelled with correct unit.

As the light intensity increases, the population ofPleurococcus sp. also increases because photosynthesis occurs more. (SPM 2008)

Answer must based on the result of the experiment not from the theory. (Refer the figure/table)
Population distribution is the total surface area covered by thePleurococcus sp. within 10 X10 cm at different light intensity. (SPM 2008)

PREDICTING (3 marks)
Predict the outcome using a relevant statement. Plus explanation.

Students must complete the given table according to the title. If the table is not provided, construct the table according to the classification given. Include all answers.

QUESTION 2 (17 marks)

AIM/OBJECTIVES (No mark, just a tick)
Write down as in the question.

Must be in a question form. (Modify the aim)

HYPOTHESIS (3 marks)
Able to state the hypothesis correctly based on the following criteria:
 State the manipulated variable
 State the responding variable
 Relate the manipulated variable and the responding variable

VARIABLES (No mark, just 3 ticks)
Write down all the 3 variables (one for each variable)

TECHNIQUE (1 mark)
In a complete sentence, write down what is observed or measured (include the instrument used). State the specific name of the technique where applicable.
Measure and record the volume of fruit juices needed to change the blue DCPIP to colourless using a syringe.
Measure and record the initial and final temperature of the water in the boiling tube using a thermometer.

List down at least 3 materials and 3 apparatuses.

Write down each step clearly and systematically.
i) Set up of materials and apparatus
ii) Operating the manipulated variable
iii) Operating the responding variable
iv) Operating the fixed variable
v) Precautions

Construct the table with the correct titles and units (results/data – no need) .

CONCLUSION (No mark, just a tick)
Repeat or modify the hypothesis sentence.

Experiment : 14 marks
Planning : 3 marks
Total : 17 marks

A study of genes

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Alleles, alternative versions of a gene. A somatic cell has two copies of each chromosome (forming a homologous pair) and thus two alleles of each gene, which may be identical or different. This figure depicts an F1 pea hybrid with an allele for purple flowers, inherited from one parent, and an allele for white flowers, inherited from the other parent.

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Mendel’s law of segregation. This diagram shows the genetic makeup of the generations in Figure 14.3. It illustrates Mendel’s model for inheritance of the alleles of a single gene. Each plant has two alleles for the gene controlling flower colour, one allele inherited from each parent. To construct a Punnett square, list all the possible female gametes along one side of the square and all the possible male gametes along an adjacent side. The boxes represent the offspring resulting from all the possible unions of male and female gametes.

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Phenotype versus genotype. Grouping F2 offspring from a cross for flower color according to phenotype results in the typical 3:1 phenotypic ratio. In terms of genotype, however, there are actually two categories of purple–flowered plants, PP (homozygous) and Pp (heterozygous), giving a 1:2:1 genotypic ratio.

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Pedigree Analysis
Unable to manipulate the mating patterns of people, geneticists must analyze the results of matings that have already occurred. They do so by collecting information about a family’s history for a particular trait and assembling this information into a family tree describing the interrelationships of parents and children across the generations—the family pedigree shows a three–generation pedigree that traces the occurrence of a pointed contour of the hairline on the forehead. This trait, called a widow’s peak, is due to a dominant allele, W. Because the widow’s–peak allele is dominant, all individuals who lack a widow’s peak must be homozygous recessive (ww ). The two grandparents with widow’s peaks must have the Ww genotype, since some of their offspring are homozygous recessive. The offspring in the second generation who do have widow’s peaks must also be heterozygous, because they are the products of Ww × ww matings. The third generation in this pedigree consists of two sisters. The one who has a widow’s peak could be either homozygous (WW ) or heterozygous (Ww ), given what we know about the genotypes of her parents (both Ww).

Cystic Fibrosis
The most common lethal genetic disease in the United States is cystic fibrosis, which strikes one out of every 2,500 people of European descent but is much rarer in other groups. Among people of European descent, one out of 25 (4%) is a carrier of the cystic fibrosis allele. The normal allele for this gene codes for a membrane protein that functions in chloride ion transport between certain cells and the extracellular fluid. These chloride transport channels are defective or absent in the plasma membranes of children who inherit two recessive alleles for cystic fibrosis. The result is an abnormally high concentration of extracellular chloride, which causes the mucus that coats certain cells to become thicker and stickier than normal. The mucus builds up in the pancreas, lungs, digestive tract, and other organs, leading to multiple (pleiotropic) effects, including poor absorption of nutrients from the intestines, chronic bronchitis, foul stools, and recurrent bacterial infections. Recent research indicates that the extracellular chloride also contributes to infection by disabling a natural antibiotic made by some body cells. When immune cells come to the rescue, their remains add to the mucus, creating a vicious cycle.

If untreated, most children with cystic fibrosis die before their fifth birthday. Gentle pounding on the chest to clear mucus from clogged airways, daily doses of antibiotics to prevent infection, and other preventive treatments can prolong life. In the United States, more than half of the people with cystic fibrosis now survive into their late 20s or even 30s and beyond.

Sickle–Cell Disease
The most common inherited disorder among people of African descent is sickle–cell disease, which affects one out of 400 African–Americans. Sickle–cell disease is caused by the substitution of a single amino acid in the hemoglobin protein of red blood cells. When the oxygen content of an affected individual’s blood is low (at high altitudes or under physical stress, for instance), the sickle–cell hemoglobin molecules aggregate into long rods that deform the red cells into a sickle shape (see Figure 5.21). Sickled cells may clump and clog small blood vessels, often leading to other symptoms throughout the body, including physical weakness, pain, organ damage, and even paralysis. The multiple effects of a double dose of the sickle–cell allele are another example of pleiotropy. Regular blood transfusions can ward off brain damage in children with sickle–cell disease, and new drugs can help prevent or treat other problems, but there is no cure.

Although two sickle–cell alleles are necessary for an individual to manifest full–blown sickle–cell disease, the presence of one sickle–cell allele can affect the phenotype. Thus, at the organismal level, the normal allele is incompletely dominant to the sickle–cell allele. Heterozygotes, said to have sickle–cell trait, are usually healthy, but they may suffer some sickle–cell symptoms during prolonged periods of reduced blood oxygen. At the molecular level, the two alleles are codominant; both normal and abnormal (sickle–cell) hemoglobins are made in heterozygotes.

About one out of ten African–Americans has sickle–cell trait, an unusually high frequency of heterozygotes for an allele with severe detrimental effects in homozygotes. One explanation for this is that a single copy of the sickle–cell allele reduces the frequency and severity of malaria attacks, especially among young children. The malaria parasite spends part of its life cycle in red blood cells (see Figure 28.11), and the presence of even heterozygous amounts of sickle–cell hemoglobin results in lower parasite densities and hence reduced malaria symptoms. Thus, in tropical Africa where infection with the malaria parasite is common, the sickle–cell allele is both boon and bane. The relatively high frequency of African–Americans with sickle–cell trait is a vestige of their African roots.

Mating of Close Relatives
When a disease–causing recessive allele is rare, it is relatively unlikely that two carriers of the same harmful allele will meet and mate. However, if the man and woman are close relatives (for example, siblings or first cousins), the probability of passing on recessive traits increases greatly. These are called consanguineous (“same blood”) matings, and they are indicated in pedigrees by double lines. Because people with recent common ancestors are more likely to carry the same recessive alleles than are unrelated people, it is more likely that a mating of close relatives will produce offspring homozygous for recessive traits—including harmful ones. Such effects can be observed in many types of domesticated and zoo animals that have become inbred.

There is debate among geneticists about the extent to which human consanguinity increases the risk of inherited diseases. Many deleterious alleles have such severe effects that a homozygous embryo spontaneously aborts long before birth. Still, most societies and cultures have laws or taboos forbidding marriages between close relatives. These rules may have evolved out of empirical observation that in most populations, stillbirths and birth defects are more common when parents are closely related. Social and economic factors have also influenced the development of customs and laws against consanguineous marriages.

Dominantly Inherited Disorders
Although many harmful alleles are recessive, a number of human disorders are due to dominant alleles. One example is achondroplasia, a form of dwarfism with a prevalence of one among every 25,000 people. Heterozygous individuals have the dwarf phenotype

Therefore, all people who are not achondroplastic dwarfs—99.99% of the population—are homozygous for the recessive allele. Like the presence of extra fingers or toes mentioned earlier, achondroplasia is a trait for which the recessive allele is much more prevalent than the corresponding dominant allele.

Dominant alleles that cause a lethal disease are much less common than recessive alleles that do so. All such lethal alleles arise by mutations (changes to the DNA) in a sperm or egg; presumably, such mutations occur equally often whether the mutant allele is dominant or recessive. However, if a lethal dominant allele causes the death of offspring before they mature and can reproduce, the allele will not be passed on to future generations. In contrast, a lethal recessive allele can be perpetuated from generation to generation by heterozygous carriers who have normal phenotypes. These carriers can reproduce and pass on the recessive allele. Only homozygous recessive offspring will have the lethal disease.

A lethal dominant allele can escape elimination if it causes death only at a relatively advanced age. By the time the symptoms become evident, the individual may have already transmitted the lethal allele to his or her children. For example, Huntington’s disease , a degenerative disease of the nervous system, is caused by a lethal dominant allele that has no obvious phenotypic effect until the individual is about 35 to 45 years old. Once the deterioration of the nervous system begins, it is irreversible and inevitably fatal. Any child born to a parent who has the allele for Huntington’s disease has a 50% chance of inheriting the allele and the disorder. (The mating can be symbolized as Aa × aa, with A being the dominant allele that causes Huntington’s disease.) In the United States, this devastating disease afflicts about one in 10,000 people.

Until relatively recently, the onset of symptoms was the only way to know if a person had inherited the Huntington’s allele. This is no longer the case. By analyzing DNA samples from a large family with a high incidence of the disorder, geneticists tracked the Huntington’s allele to a locus near the tip of chromosome 4.

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Meiotic nondisjunction. Gametes with an abnormal chromosome number can arise by nondisjunction in either meiosis I or meiosis II.Alterations of chromosome structure. Vertical arrows indicate breakage points. Dark purple highlights the chromosomal parts affected by the rearrangements.

Down syndrome.The child exhibits the facial features characteristic of Down syndrome. The karyotype shows trisomy 21, the most common cause of this disorder.

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The articles you must read.

Spasms or muscle cramps

If you've ever had muscle spasms or muscle cramps, you know they can be extremely painful. In some cases, a muscle may spasm so forcefully that it results in a bruise on the skin. Most muscle spasms and cramps are involuntary contractions of a muscle. A serious muscle spasm doesn't release on its own and requires manual stretching to help relax and lengthen the shortened muscle. Spasms and cramps can be mild or extremely painful. While they can happen to any skeletal muscle, they are most common in the legs and feet and muscles that cross two joints (the calf muscle, for example). Cramps can involve part of a muscle or all the muscles in a group. The most commonly affected muscle groups are:
   Back of lower leg / calf (gastrocnemius).
   Back of thigh (hamstrings).
   Front of thigh (quadriceps).
   Feet, hands, arms, abdomen

Muscle cramps range in intensity from a slight twitch or tic to severe pain. A cramped muscle can feel rock-hard and last a few seconds to several minutes or longer. It is not uncommon for cramps to ease up and then return several times before they go away entirely.

What Causes Muscle Cramps
The exact cause of muscle cramps is still unknown, but the theories most commonly cited include:
   Altered neuromuscular control
   Electrolyte depletion
   Poor conditioning
   Muscle fatigue
   Doing a new activity

Other factors that have been associated with muscle cramps include exercising in extreme heat. The belief is that muscle cramps are more common during exercise in the heat because sweat contains fluids as well as electrolyte (salt, potassium, magnesium and calcium). When these nutrients fall to certain levels, the incidence of muscle spasms increases. Because athletes are more likely to get cramps in the preseason, near the end of (or the night after) intense or prolonged exercise, some feel that a lack of conditioning results in cramps

Treating Muscle Cramps
Cramps usually go away on their own without treatment, but these tips appears to help speed the healing process:
   Stop the activity that caused the cramp.
   Gently stretch and massage the cramping muscle.
   Hold the joint in a stretched position until the cramp stops.

Preventing Muscle Cramps
Until we learn the exact cause of muscle cramps, it will be difficult to say with any confidence how to prevent them. However, these tips are most recommended by experts and athletes alike:
   Improve fitness and avoid muscle fatigue
   Stretch regularly after exercise
   Warm up before exercise
Stretch the calf muscle: In a standing lunge with both feet pointed forward, straighten the rear leg.
Stretch the hamstring muscle: Sit with one leg folded in and the other straight out, foot upright and toes and ankle relaxed. Lean forward slightly, touch foot of straightened leg. (Repeat with opposite leg.)
Stretch the quadriceps muscle: While standing, hold top of foot with opposite hand and gently pull heel toward buttocks. (Repeat with opposite leg.)

Most muscle cramps are not serious. If your muscle cramps are severe, frequent, constant or of concern, see your doctor.

Heart Diseases

Hardening of arteries
   Tunica intima thickens with deposits of Cholesterol, Fibrous (scar) tissue, Dead muscle cells, Blood platelets        
      Arteries become less elastic and partially narrowed
        ↑BP which in turn accelerates atherosclerosis
         Leads to endothelium damage and weak walls

   Excess cholesterol leaks from lipoproteins (LDLs)
   Deposited on arterial walls
   Macrophages (white blood cells) are trapped within cholesterol
   Release free radicals which damage the arterial wall
   Activates blood platelets which stick to damaged areas releasing clotting factors (thromboxanes)
   Forms a plaque which may rupture to produce a thrombus
   Circulating thrombus is called an embolus
   Embolus may lodge elsewhere in the circulation (brain, heart arteries)
   NB: healthy arteries produce anti-clotting factors (prostaglandins) → don't form clots

Factors that aggravate atheroma formation / atherosclerosis:
   Hypertension (↑BP)
   Smoking (release of free radicals)
   High LDL and low HDL
   NB: they all cause endothelial damage

   Weak arterial walls may burst leading to severe loss of blood (haemorrhaging)
   Brain aneurysm is called a stroke

Deep Vein Thrombosis
   Clots are formed by
   Endothelial damage (see atherosclerosis)
   Altered blood components (dehydration, too many platelets)
   Altered blood flow (stasis of veins) → this is what causes DVT
      Prolonged immobility
      Such as paralysis, long-distance flights, lying down for weeks after surgery
   Thrombus often originates in calf veins
   Inflammation of vein walls → destroys vein valves
   Causes leg pain, swelling, and redness
   Elastic support stockings required for life
   Prevented by taking aspirin or warfarin which inhibit blood clotting

Coronary Heart Disease
   Atherosclerosis causes arteries to become narrowed
      More force required to move blood through narrowed vessels
      Blood pressure increases
   Stable angina
      ↑exercise leads to ↑oxygen requirements by heart
      Narrowed arteries prevent more blood to pass through
      Shortage of blood to heart muscle causes chest pain
      Cells do not die as some blood can still pass through
      Pain only occurs during activity but not at rest

Myocardial infarction (MI)
   Coronary artery is totally blocked by a thrombus/embolus
   No blood supply to heart muscle and cells die
   Irreversible if not treated within 90min

Heart failure
   Prolonged blockage of artery causes damage to heart muscle
   ↓contractions / ↓cardiac output / ↓pressure generated / less blood leaves heart
   More blood is stored:
       on the right side of the heart → enlarged heart
       in veins → swollen legs and enlarged liver

  Needed for
     Vitamin D production in skin
     Sex hormone production in gonads and adrenal glands
     Making cell membranes
     Produce bile acid (salts)
  Has properties similar to fats → soft, waxy, and insoluble (difficult to remove if deposits form)
  Transported in blood from liver to tissues
  Safe transport is needed due to its insolubility
  Achieved by lipoproteins, which are soluble fatty proteins
  These are wrapped around cholesterol
  Normally, only small amounts of free cholesterol escape

   Low density lipoproteins
  Carries cholesterol from liver to tissues
  Normally, some cholesterol 'leaks' from the lipoprotein and is absorbed to build cell membranes
   Excess LDL/cholesterol → too much cholesterol leaks out and causes atherosclerosis

   High density lipoprotein
   Picks up cholesterol from arterial walls and carries it away from tissues
   Travels to liver where cholesterol is removed with bile

↓antitoxidants (vitamins), more damage due to release of free radicals by phagocytes
Nicotine constricts arteries causing platelets to stick together → vasoconstriction → heart must work harder to force blood through → increases BP
↑BP causes damage to blood vessel lining / endothelium / collagen
Leads to rise on blood platelets and makes them more sticky / form a plug / adhere to collagen fibres
Release of thromboplastin/thrombokinase
Fibrinogen converted to insoluble fibrin
Platelet plug trapped by fibrin mesh
Raises conc. of fibrinogen (in blood) → increased risk of clotting
↑LDL causes more cholesterol to leak out in blood
Carbon monoxide reduces the efficiency of the blood in terms of carrying oxygen
Haemoglobin combines with CO more readily than with oxygen → forms carboxyheamoglobin
Associated with plaque formation
Principle CHD = heart muscle receives inadequate amount of blood or oxygen/(coronary) blood supply reduced

Beta blockers reduce heart rate and reduce oxygen required by heart
Aspirin prevents blood clotting and thrombosis formation
ACE inhibitors stabilize plaques → prevent thrombus to break off
Statins reduce LDL and increase HDL
Deflated balloon-like device is passed up to the heart via the aorta
Guided into damaged coronary artery and inflated to stretch the artery
Heart by-pass graft
Leg veins and arteries from chest are used to by-pass the blocked region of the coronary artery
Involves open heart surgery
Reperfusion therapy after a myocardial infarction
Angioplasty done within 90 minutes of onset of chest pain
May prevent irreversible damage to the heart muscle

1. Screen population for
   High BP
   High cholesterol
   Uncontrolled diabetes
   Smoking? Unhealthy diet? No exercises?
   Men over 55 and women over 65 are at highest risk
2. Monitor the behaviour of the heart during exercise
   Difficult but encouraging the population to adopt a more healthy lifestyle from an early age is important
   Often leads to changes in diet and weight management
3. Giving up smoking and reducing alcohol intake
    Reduces blood pressure
    Coronary heart disease is a long-term degenerative disease, starts at birth



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.

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.

Teacher Dearest...2010

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.

DID YOU KNOW THAT.................

  1. Nucleus - contains DNA
  2. Nucleolus - in nucleus, manufactures ribosomes
  3. Endoplasmic reticulum - move materials from one part of the cell to another
  4. Golgi apparatus - where proteins are converted to their final form
  5. Lysosomes - contain digestive enzymes
  6. Chloroplasts - contain pigments important to photosynthesis
  7. Mitochondria - site of ATP production
  8. Ribosomes - manufacture of proteins
  9. Centrioles and microtubules - support, cell locomotion, forming spindle in nuclear division
  10. Cell wall - support, prevents cell from bursting by taking in too much water
  11. Osmosis: the net movement of water molecules through a partially permeable membrane from an area of higher water potential to an an area of lower water potential.
  12. Facilitated diffusion: This is where polar molecules are transported across membranes. Molecules bind with transport proteins which change shape and move the molecules across the membrane. No metabolic energy is required.
  13. Examples of active transport: the calcium pump (skeletal muscles), the sodium-potassium pump (nerve cells).
  14. Endocytosis: An active process whereby substances are taken into the cell by infoldings of the surface membrane. (Exocytosis is similar.)
  15. Mitosis: Mitosis is a type of cell division where the daughter cells have the same number of chromosomes as the parent cell and are genetically identical to the parent cell. Mitosis takes place in four stages: prophase, metaphase, anaphase and telophase.
  16. During prophase, each chromosome forms two chromatids joined by a centromere. Two centrioles begin to move forming a spindle and the nuclear envelope breaks down.
  17. During metaphase, the chromosomes are attached to the spindle fibres and line up at the equator of the cell.
  18. During anaphase, the centromeres split and the chromatids are pulled to opposite poles of the cell.
  19. During telophase, the nuclear envelope reforms and the cell membrane narrows at the middle, forming two daughter cells 
  20. Sucrose = glucose + fructose; main form in which carbohydrate is transported in plants 
  21. Maltose = 2 glucose; found in some germinating seeds eg barley
  22. Lactose = glucose + galactose; found in milk
  23. Lipids - insoluble in water, soluble in organic solvents
  24. Fats & oils - compounds of glycerol and fatty acids
  25. Structure of proteins 
  • Primary - Order of the amino acids
  • Secondary - The way the chain folds/turns on itself due to hydrogen bonding
  • Tertiary - Cross-links including hydrogen bonds, inonic bonds and sulphur bridges
  • Quaternary - The arrangement of two or more polypeptides eg haemoglobin
26.Collagen - fibrous protein; great tensile strength; found in bones, tendons, skin etc; structure = triple helix
27.Insulin - globular protein, folded chain held together by 2 disulphide bridges with the loop removed

December 30, 2009

3 hari lagi......

3 hari lagi skolah akan dibuka semula,so 3 hari lagi akan tamatlah percutian yang menyeronokkan ni...kadanng kala rasa bosan pulak.sebab nothing to do....cuma yang menjadi penghibur hari, ammar n batrisyia yang tak pernah rasa penat bermain,minum susu sambil tengok tv dan diselang seli dengan tangisan...bergaduh berebut mainan,berebut makanan.kadang kala terdengar suara berdekah dekah ketawa membuatkan ku rasa istemewanya menjadi ibu kepada dua orang cahayamata ini.mmmm kadang2 aku yang jadi macam budak2,berebut channel tv astro ngan ammar.....masam muka anak aku sulong...tapi kejap ajer..lepas tu mai pujuk balik hati ibu minta dibuatkan susu untuknya...

3 hari lagi,kebosanan aku akan terisi dengan kesibukan kerja2 di skolah yang semakin hari semakin bertambah.sibuk dengan tugas2 dirumah,amik anak dari skolah,hantar tuition...amik dari tuition..akan jadi rutin hidupku.tugas ini ku kongsi bersama hubby ku...kadang aku yang jadik bas skolah,kekadang hubbyku pulak yang jadi bas year he is 6...trisyia pulak 2.kejap ja masa berlalu......

December 28, 2009

nukilan rasa from the beginner: baru blajar create blog sendiri...tak pandai lagi

nukilan rasa from the beginner: baru blajar create blog sendiri...tak pandai lagi

December 27, 2009

baru blajar create blog sendiri...tak pandai lagi

Saat ini diriku membuka,membaca,melihat foto di blog sahabat sahabat lamaku...terdetik dihatiku untuk memiliki blogg sendiri,tapi...apa yang hendak ku tulis...berbekalkan sedikit ilmu..ku buka ku cari,ku explore apa yang patut....cuba try lah dulu....baru balajar nak menulis ...nanti dah lama pandai lah
Macam mula2 ku kenal fbook..dulu tak tahu,dah tahu explore seronok pulak dapat jumpa balik member2 lama, xfriend masa tadika,skolah rendah,skolah menengah,x matrik,x usm.....dan macam2 x lah...upsssss