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Friday, 3 July 2015

The Science of Effective Classroom Communication

Teaching is a noble profession and all teachers whether teaching in the primary, secondary or post secondary educational institutions are all noble men and women who are helping in creating and shaping the society. Most of the teaching and learning in educational institutions takes place in the classroom where there is a close contact between the teacher and the student. It is the oldest method of teaching known to man but it is also a very scientific model of teaching because it takes into consideration several factors such as the psychology of the student, the learning environment, the teaching aids, the infrastructure and the psychic disposition of both the teacher and the student even outside the classroom environment.

Here, we are going to examine the science involved in classroom communication during teaching and learning with a view to identifying those germane verbal communication tips needed for teaching to be effective in the classroom.

First of all, aim at winning the hearts and minds of your students. This is the prelude to winning their ears. You can achieve this as a teacher by making your students your friends, been genuinely concerned about their welfare and even asking them personal questions. Identify their different temperaments:- choleric, melancholic, sanguine and phlegmatic. Your first encounter with your students as a teacher should not always be based on academics……it is supposed to be a period where you get acquainted with them on a personal level.

Secondly, you have to determine your objectives as a teacher. You have to identify from the onset what you want to pass across to your students.

Thirdly, you have to decipher the knowledge base of the students on topic you are introducing. Do your students have a prior idea or understanding about the topic at hand?

Fourthly, planning the communication is key to effective teaching. The examples and analogies to use while teaching and communicating is taking into consideration including the cultural, religious and traditional beliefs of the students; how to proceed and how to conclude within the stipulated timeframe.

Your psychological and emotional stability is germane while communicating with your students. As a teacher, you must be in the right emotional of mind and aim at minimizing interruptions while teaching. This means that you must be logical, maintain eye contact with your students, and be appealing and interesting.

Lastly, you must employ the feedback mechanism. You must evaluate the impact of your communication on the students….did they understand the topic taught? Encourage them to ask you questions in areas they do not understand and give detailed explanations with concrete references. Check their notes or recording devices and set a short test exam to further evaluate their level of comprehension at the end of the lesson.

Oswald Avery and his evidence of the Involvement of Nucleic Acid in Inheritance

Nucleic acids are molecules that contain information and are also capable of replication. It refuted the once held claim that only protein was capable of carrying genetic information that can be transferred because of its structural diversity. Oswald Avery of the Rockefeller institute in the city of New York presented evidence that showed nucleic acids rather than proteins were responsible for carrying genetic information.

The bacteria that causes pneumonia, pneomococcus , exists in two distinct forms--- the capsulated and the non capsulated forms. The capsulated forms have their cells surrounded by a thick capsule while the non capsulated form has this thick capsule completely missing. Oswald Avery and his colleagues then prepared a medium of disrupted capsulated bacteria which did not contain any living bacteria cells but only the chemicals extracted from them. He introduced non-capsulated bacteria into this medium and allowed it to grow. He found quite remarkable that the non-capsulated bacteria developed capsules.

The conclusion here is that a chemical component in the extract of the capsulated bacteria was capable of bringing about a permanent and inheritable change in the non-capsulated strains. What then is this chemical component? Avery later conducted several other experiments on the medium by systematically isolating and purifying the different chemical constituents and him and his colleagues were able to show and confirm that nucleic acids were the active agent!


What exactly is gastrulation? This technical term may seem very unfamiliar even to the very learned because it is rarely used in discussions and appears less often in texts when compared to other technical terms used in biology or medicine. Gastrulation means the ‘formation of a gut’ or better put, ‘gut formation’. It is the process that takes place as a result of the various movements of the cell and this cell movement leading to gastrulation varies from one species to the other. In a simple form, gastrulation involves invagination at one end of the blastula(a spherical mass of cell) which has a fluid filled cavity referred to as blastocoel. It’s just like pushing a tennis ball into the blastula with the resultant formation of a two layered cup shaped structure known as gastrula. Here, the outer cell layers known as the ectoderm gives rise to the associated structures and the skin; the inner cell layers known as the endoderm forms the lining of the gut including other structures.

When gastrulation occurs, it results in the total obliteration of the blastocoels which is replaced by an entirely new cavity referred to as the archenteron(primitive gut). The opening of the archenteron to the exterior where the invagination has occurred is called blastopore and this blastopore represents the future posterior end of the embryo. During gastrulation, the lips of the blastopore represent that point where cells that initially lined the blastula, turn inwards and forms the lining of the archenteron. These cells such as the chorda-mesoderm are destined to give rise to the notochord and the mesoderm respectively.

Interferon And The Formation Of Antibodies

Interferon is a protein extracted from cells which have been found to prevent the proliferation and multiplication of viruses. They are non specific in their action unlike antibodies and thus effective against a wide range of viruses. Interferons are effective against the influenza virus and the polio virus and they are generally more effective in the same species of animals in which it is manufactured.

It has been found that interferons confer protection against the Vaccinia virus on chick embryos and rabbit. The explanation here is that whenever a virus invades ac cell, it alerts other cells of the presence on the virus and they are therefore armed against the invader, consequently conferring protection on the organism. 

Interferon is non toxic, does not stimulate antibody production and lacks specificity. These features or qualities make interferon a novel protein in conferring immunity to a wide range of diseases, even to man. However, the shortcomings of interferon is that it would need to be produced in very large quantities and must come from human cells(to be used on humans) or from closely related species such as the chimpanzee.

                                                  Formation of Antibodies

Antibodies are formed as a result of the entry of micro-organisms that produce antigens(protein macromolecules) which in turn cause the lymphocytes(white blood cells) to produce corresponding antibodies. Antibodies combine in some way to neutralize the effects of antigens and in the process cause the destruction or death of the invading organism. They can achieve this by adhering to the surface of the micro–organisms making them to clump together or agglutinate, or cause them to disintegrate(lysis) and the remains of the lyzed organism can then be ingested by phagocytes.
There are other types of antibodies such as opsonins which are usually absorbed onto the surface of micro-organisms making them easier to be engulfed by phagocytes. There is also the antitoxins which can neutralize toxins and the precipatins which cause the aggregation of antigen molecules which ultimately leads to the formation of a precipitate.

Operating The Gasoline Engine/Generator

It is absolutely important that you do not connect any electrical appliance to the engine prior to starting it. When you are ready to start the engine, just turn the fuel cock ON and turn the engine switch ON. Next you turn the choke lever to the position of ‘choke’. Note that if the engine is already warm, there would be no need for this and you can just leave the choke lever in the ‘RUN’ position.

Starting the engine is not a difficult procedure. Just pull the starter handle slowly and gently until you feel a resistance which is known as the compression point. Next, return the handle to its initial position and pull it swiftly making sure you do not fully pull out the rope. Note that after the engine has started, you should allow the handle to return to its original position while you are still holding the handle. Warm up the engine for a while usually a few minutes without any load and then turn the choke back to the operating position(RUN).

                                       Caution While Using Electrical Power

Make sure the electrical appliances to be plugged into the generator are turned off before you connect into the generator.

Ensure that the total load is within the output rating of the generator.

Ensure that the socket load current is within the socket rated current.

If you intend to get power from a TWIST LOCK receptacle, just insert the plug into the receptacle and turn the TWIST LOCK clockwise to lock it.

Sometimes the no-fuse breaker or circuit breaker may turn off during operation. When this happens, it means the generator is overloaded or the appliance is defective. All you need do is to stop the generator immediately and check the appliance or generator for defects and possible repairs.

                                                           Trouble Shooting

If your gasoline Engine or generator fails to start, then you can look out for any of these trouble shooting and the solutions you can apply

1. Choke lever in RUN position—set it to choke position

2. No fuel in the combustion chamber

3. Clogged carburetor—clean the carburetor

4. No fuel in fuel tank--- refill fuel tank

5. Foreign object or dirt in fuel cock

6. Locked fuel cock— set to ON position

7. Insufficient engine oil---- refill engine oil

8. Poor spark--- clean the spark plug by removing the carbon clogging it

9. Insufficient compression--- caused by worn out piston and cylinder, loose cylinder head nuts and damaged gasket. In all these consult the dealer or technician or replace gasket and tighten nuts firmly.

10. No electricity is generated at the receptacle---check the AC protector and make sure it is set in the ON position, check whether the appliance is connected to the generator when the engine is started and then disconnect it from the receptacle. Also check for loose connections and secure appropriately.

Control Functions of A Gasoline Generator And Per-Operation Checks

The engine switch of the gasoline generator operates the machine. This means that when the ignition system is ON, the engine can be started and when it is set OFF, the engine will not run. The AC or DC switch turns off automatically when the load capacity of the generator exceeds the rated output of the generator. In this circumstance, it is necessary to reduce the load to within the rated output of the generator especially if the protector is turned off.

                                     Components of A Gasoline Generator

Fuel tank
Fuel cock
Spark Plug
Fuel tank cap
Air filter cover
Choke lever
Recoil starter
Oil filter cap
Pilot lamp
Oil drain plug
Engine switch
AC socket
Ground terminal
Volt meter
DC socket
AC protector
DC protector

Per Operation checks are checks that are done each time the generator is used. This means that each time the generator is to be operated the fuel level must be checked and possibly refilled. It is recommended that unleaded fuel be used for gasoline generators and the fuel tank be filled to its capacity if it is to be operated for a long time. It is important to use the fuel filter while refueling to avoid dirt from entering in to the carburetor.

It is absolutely important not to refill the tank while the engine is in operation.

Wipe off all spilled fuel from the tank surface before starting the engine and always keep open flames away.

Ensure that the generator stands on affirm and flat surface while refilling the engine oil. The engine must not be running while refilling is going on. It is also very necessary to refill oil to the upper level line if it falls below the lower level line. Do not screw in the oil filter cap while checking the oil level.
The recommended engine oil is API service “SE” or “SF”. If these two are not available then you can use “SD”.

As a point of warning, you must ensure that oil level is checked before you operate the engine, else the engine gets damaged.

Safety Precautions While Operating A Gasoline Generator

The gasoline generator is a mechanical device that converts chemical energy into electrical energy to power homes, offices and industrial machinery. It comes in various sizes, shapes, color and capacity. The gasoline generator uses gasoline as fuel(petrol) and is common in countries with underdeveloped electricity infrastructure. However, there are several safety precautions that must be taken in order to run a gasoline generator efficiently and devoid of danger to the user or members of the household.

                                                         Safety Precautions

1. You must realize that exhaust fumes are poisonous. Therefore, you must never attempt to operate a gasoline generator in an enclosure or in a place with limited aeration or ventilation. Not adhering to this rule may cause suffocation, unconsciousness or even death within a few minutes due to the inhalation of carbon monoxide.

2. Gasoline is highly flammable, so it is absolutely necessary to put off the engine before re-fueling. Never refuel in a vicinity where there is an open flame or fire. It is also very necessary not to spill any fuel on the engine while re-fueling or allow fuel to touch the coil or other engine parts of this machine.

3. If for any reason or circumstance, you inhale fuel vapor or swallow fuel, or even allow it to get into your eyes, then you must see a doctor immediately. Wash off any fuel spill on your skin or on your clothes with plenty of soap and water.

4. Remember to transport the generator in an upright position to avoid it tilting and expelling fuel from the fuel tank or carburetor.

5. Keep the generator at least 3feet(1M) away from  walls and buildings or any other equipment else the equipment may overheat. 

6.  Always ensure that flammable objects are taken far off the exhaust outlet of the generator when in operation.

7. Avoid operating the machine in places where children can easily reach it and desist from operating the machine with a dust cover.

8. Under no circumstance should you operate the generator in rain or in snow even when the generator is earthed.  Avoid touching the generator with wet hands else electric shock or electrocution may occur and be sure to ground i.e earth the generator.

When you earth your generator, be sure to use a lead wire of sufficient current capacity and of diameter of 0.12mm(0.005inches)per amperes. Therefore, a 1.2mm wire would have a current carrying capacity of 10amperes.

9. Avoid connecting the gasoline generator in parallel with any other electricity generating device or any other generator.

10. The battery of gasoline generator emits hydrogen gas which is capable of exploding if exposed to an electric arcing or an open flame.

Biological Explanation of Allergy and Stress

People often complain about stress conditions they are subjected to and allergy or allergic reactions to substances, fumes or objects. Sometimes, the body over reacts to very minute traces of a foreign substance which in actual fact may even be harmless. In this circumstance, the individual is said to be allergic.

Skin itching, skin rashes, headaches, sneezing, and difficulty in breathing are well known symptoms of allergic reactions. However, the underlying causes of these allergic reactions are largely unknown but what is certain is that the antigen-antibody reaction occurs on the surface of tissue cells, which consequently become highly permeable and may cause it to burst resulting in histamine being released from the cells especially from the mast cells in connective tissues.

Histamine is responsible for itching on the skin, flushing of the skin, dilation of the capillaries, headaches and constriction of the bronchi. Histamine also increases the permeability of the capillaries, which consequently leads to an increase in the rate of formation of tissue fluid that causes swelling of tissues and organs. In hay fever for instance, antibodies react against pollen in the nostrils causing a localized damage to the nasal tissues and the subsequent release of histamine. These kinds of allergies can be combated by giving the patient anti-histamine drugs.

Allergy and inflammation both constitute stress. Interestingly, stress is combated by the secretion of the hormone known as cortisone from the adrenal cortex. Cortisone is responsible for the shrinkage of lymph nodes which lowers the number of white blood cells. cortisone also combats inflammation and healing of wounds and it also brings about a whole lot of reactions which enables the animal to adapt to stress and stress conditions and prevent its anti-infection mechanisms from been too widespread and pronounced.

Production of cortisone is triggered by adreno-cortico-tropic hormone(ACTH) from the anterior end of the pituitary gland and then acted upon by some stress causing agents such as bacteria. Cortisone also controls the stressful effect of shock. In this situation of shock, adrenalin is released from the adrenal medulla and one of the effects of adrenalin is to increase the flow of ACTH from the pituitary thereby increasing and promoting the secretion of cortisone from the adrenal cortex.