The Root Bridge

Homeostasis is a very important topic in biology (5090) and there are multiple concepts in this topic which you need to learn.  First of all, you should know that what is meant by homeostasis?  The system of a body which is responsible for the maintenance of the internal environment is known as homeostasis .  In other words, it is the ability to maintain a stable state that continues despite the changes outside. This system ensures the survival of all species from plants to animals.  This was all about the introduction of this topic. Now, let's move into further details and learn about some other topic as well.  Negative feedback:  To maintain a constant internal environment, a significant principle known as negative feedback occurs. In other words, it is the principle on which homeostasis works.  In biological systems, negative feedback  (a regulatory mechanism) is a type of regulation that occurs when a specific stimulus (change) is detected....

The turning effect of forces is a very important topic in Physics and there are multiple topics in this chapter which you need to learn.  First of all, you should know that a force may cause an object to rotate (clockwise or anticlockwise) around its pivot (a central point or shaft where an object turns).  This is known as the turning effect of a force or the moment of the force.  The turning effect of a force is mainly dependent upon two factors which are: The magnitude of the force The perpendicular distance from the pivot to the line of action of the force The moment of a force (torque):  The torque (moment of a force) is the product of the force and the perpendicular distance from the line of action of the force to the pivot (central point).  In terms of an equation, this can be summed up as: moment of a force = force (F) x distance (d) M = F x d The SI unit for torque (moment of a force) is newton metre (N m) because the symbol for force is newton and th...

Speed of reaction is a very important topic in Chemistry and there are multiple concepts with which you should know to ace your exams.  Rate of reaction refers to the speed at which a chemical reaction proceeds (takes place) and this speed can vary dramatically.  The speed at which a chemical reaction takes place is mainly dependent upon two factors. Those are: Frequency of collisions :  The more often molecules collide with each other, the greater the rate of reaction.  The energy of collisions :  When the molecules strike each other with greater energy, the reaction proceeds faster. In other words, the forcefully the molecules collide, the greater will be the rate of reaction.  This was all about the introduction of this topic. Now, let's discuss some important concepts about this topic.  How do we measure the speed of a reaction:  To know the rate at which the reactants are utilised or the rate at which the products are formed, w...

What do we mean by electromagnetic (EM) waves?  The electromagnetic waves (also known as EM waves) are formed as a result of the vibrations between the electric field and magnetic field.  In simple words, these are the waves of the electromagnetic field which make up a family of waves known as the electromagnetic spectrum.  The EM waves, such as radio , micro , ultraviolet and X-rays , propagate through space carrying electromagnetic radiant energy.  Let me further explain this with the help of an example. The light from a lamp in your house is a type of electromagnetic radiation. Similarly, the waves travelling from the radio station are also a type of electromagnetic radiation.  In the electromagnetic spectrum (refers to the range of frequencies of the electromagnetic radiations in order with their respective wavelengths), the EM waves are arranged in order of their frequencies and wavelengths.  Radio wave (which have the longest wavelength and the lo...

  The atmosphere and environment is a very important topic in GCE O level Chemistry (5070). There are multiple concepts in this chapter that need to be addressed.  Therefore, let's dive into the topic without further introductions and start from the very beginning of this chapter.  What is the atmosphere? Our earth is surrounded by a layer or layers of gases known as the atmosphere.  In other words, atmosphere refers to the layer of air that is held by gravity. You should know that without the atmosphere, there would be no life on earth.  But, why is that so? Let me explain that in detail.  The atmosphere is a protective layer that serves as a shield to the earth and protects it from the harmful radiations from the sun. This action ensures that an optimum temperature is maintained on earth.  In other words, due to the atmosphere, the climate of the earth is moderate and it is a major reason why life exists on the earth.  We discussed ear...

The topic of mass, weight and density is very important in GCE O Level physics because this topic contains some really useful concepts.  So, let's start (from the beginning) without further introductions and let me explain these terms, like "mass" and "weight" to you in detail.  Before understanding the concept of mass and weight, you have to remember that these two quantities, mass and weight, and not similar. How are they different? Let me tell you.  What is mass?  Mass refers to the amount of matter in a body. In other words, mass is the quantity of matter in a body. Since this quantity does not change with the location or shape, mass remains the same everywhere.  For example, your mass on the earth and mars will be the same because the location will not affect the "quantity of matter" of a body.  Mass is measured in various units but the SI (international system of units) is the kilogram (kg). However, other units such as gram (g) are ...