Explanation Text

EXPLANATION
Purpose: To explain the processes involved in the formation or working of natural or socio-cultural phenomena.

Generic Structure:

1.      General statement

2.      Explanation

3.      Closing

Dominant Language Features:

1.      Using Simple Present Tense

2.      Using action verbs

3.      Using passive voice

4.      Using noun phrase

5.      Using adverbial phrase

6.      Using technical terms

7.      Using general and abstract noun

8.      Using conjunction of time and cause-effect.

Photosynthesis

What is photosynthesis? Photosynthesis is a food-making process that occurs in green plants. It is the chief function of leaves. The word photosynthesis means putting together with light. Green plants use energy from light to combine carbon dioxide and water to make sugar and other chemical compounds.

How is the light used in photosynthesis?

The light used in photosynthesis is absorbed by a green pigment called chlorophyll. Each food-making cell in a plant leaf contains chlorophyll in small bodies called chloroplasts. In chloroplast, light energy causes water drawn form the soil to split into hydrogen and oxygen.

What are the steps of photosynthesis process? Let me tell you the process of photosynthesis, in a series of complicated steps, the hydrogen combines with carbon dioxide from the air, forming a simple sugar. Oxygen from the water molecules is given off in the process. From sugar together with nitrogen, sulphur, and phosphorus from the soil-green plants can make starch, fat, protein, vitamins, and other complex compounds essential for life. Photosynthesis provides the chemical energy that is needed to produce these compounds. 

Flying Kites

A kite is an object which is made from a light material stretched over a frame. Due to its light material a kite will lift off the ground and fly when it is tilted into the wind.

A kite is uses wind to make it fly because it is heavier than air. When wind travels over the surface of the kite, it is split into two streams of air. One stream of the air goes over the kite while the second stream goes under the kite.

The upper stream creates an area of low pressure above the kite. The lower stream hits the kite at a shallow angle and creates an area of high pressure.

The high pressure area has a pushing effect while the low pressure area has a pulling effect. The combination of push and pull can create enough force to lift the kite into the air.

Kites have been known for thousand of years. They are used for military or scientific purposes. Today’s kites are much used for leisure and competition.

How Earthquakes Happen

Earthquake is one of the most destroying natural disasters. Unluckily it often happens in several regions. Recently a horrible earthquake has shaken West Sumatra. It has brought great damages. Why did it occur? Do you know how an earthquake happens?

Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves. It makes the ground shake. When two blocks of rock or two plates are rubbing against each other, they stick a little. They don't just slide smoothly. The rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up. When the rocks break, the earthquake occurs.

During the earthquake and afterward, the plates or blocks of rock start moving, and they continue to move until they get stuck again. The spot underground where the rock breaks is called the focus of the earthquake. The place right above the focus is called the epicenter of the earthquake. 

How Chocolate is made

Have we wondered how we get chocolate from? Well this time we will enter the amazing world of chocolate so we can understand exactly we are eating.

Chocolate starts a tree called cacao tree. This tree grows in equatorial regions, especially in place such as South America, Africa, and Indonesia. The cacao tree produces a fruit about the size of a small pine apple. In side the fruits are the tree's seeds. They are also known as coco beans.

Next, the beans are fermented for about a week, dried in the sun. After that they are shipped to the chocolate maker. The chocolate maker starts by roasting the beans to bring out the flavors. Different beans from different places have different qualities and flavors. So they are often shorted and blended to produce a distinctive mix.

The next process is winnowing. The roasted beans are winnowed to remove the meat nib of the cacao bean from its shell. Then the nibs are blended. The blended nibs are ground to make it a liquid. The liquid is called chocolate liquor. It tastes bitter.

All seeds contain some amount of fat and cacao beans are not different. However, cacao beans are half fat, which is why the ground nibs from liquid. It is pure bitter chocolate.

Explanation Text about Tsunami

The term of “tsunami” comes from the Japanese which means harbors ("tsu") and wave ("nami"). A tsunami is a series of waves generated when water in a lake or a sea is rapidly displaced on a massive scale.

A tsunami can be generated when the sea floor abruptly deforms and vertically displaces the overlying water. Such large vertical movements of the earth's crust can occur at plate boundaries.

Seductions of earthquakes are particularly effective in generating tsunami, and occur where denser oceanic plates slip under continental plates. As the displaced water mass moves under the influence of gravity to regain its equilibrium, it radiates across the ocean like ripples on a pond.

Tsunamis always bring great damage. Most of the damage is caused by the huge mass of water behind the initial wave front, as the height of the sea keeps rising fast and floods powerfully into the coastal area. 

Explanation Text about Season

Seasons come to us regularly. We have probably noticed that it gets warmer in summer or dry season while it get colder in the winter or wet season. However do we know how these seasons change?

Seasons happen and change every year. This happens because the earth tilts back and forth as it goes around the sun. During the summer, the earth tilts toward the sun. It makes half of the earth hotter. This condition is what we call summer. During the other half of the year, the earth tilts away from the sun. As a result, it makes that half of the earth cooler. This cool condition is then what we call winter.

The different parts of the world have the same season at different times. In the northern half of the world, winter happens during the months of December, January and February. The regions are such North America and Europe. In the other hand, the southern half of the world has winter during the months of June, July and August. The regions are like South America and Australia. How does this difference happen? The same season happens at different times because the top and bottom halves of the earth tilt away from the sun at different times. 

How Cell Phone Work

A cell phone is a great gadget in this modern world. What is a cell phone? A cell phone is actually a radio in certain way. Like a radio, by a cell phone we can communicate to other people in real time. Million people use cell phone for their communication. Even nowadays, people use cell phones to communicate in voice, written and data. Alexander Graham Bell is the person who makes great change in the way people communicate to each other. He invented a telephone in 1876. While wireless radio was formally known in 1894 presented by Guillermo Marconi. By these two technologies, then a cell phone was born. However do you know how actually cell phones work?

This short explanation on how a cell phone work is really wonderful. A cell phone or in long term "cellular telephone' works by transmitting signals of radio to towers of cellular. The towers are networked to a central switching station. The connection usually uses wire, fiber optic-cables, or microwave.

Then the central switching station which handles calls in certain given area is directed connected to the wire-based telephone system. Cellular’s are pick up by the towers and relayed to another cellular telephone user or the user of wire-based telephone network.

The towers vary in the capacity and capability to receive signals. Some can receive the signal from short distance and the others can receive more distance. However, there is usually more than one tower in certain given area so that the system can handle the increasing telephone traffic. 

Rain Happen

Rain is the primary source of fresh water for most areas of the world, providing suitable conditions for diverse ecosystems, as well as water for hydroelectric power plants and crop irrigation.

The phenomenon of rain is actually a water circle. The concept of the water cycle involves the sun heating the Earth's surface water and causing the surface water to evaporate. The water vapor rises into the Earth's atmosphere. The water in the atmosphere cools and condenses into liquid droplets. The droplets grow until they are heavy and fall to the earth as precipitation which can be in the form of rain or snow.

However, not all rain reaches the surface. Some evaporates while falling through dry air. This is called virga, a phenomenon which is often seen in hot, dry desert regions. 

Acid Soil

Soils with a pH of less than 7.0 are acid. The lower the pH, the more acid the soil. When soil pH falls below 5.5, plant growth is affected. Crop yields decrease, reducing productivity

Soils provide water and nutrients for plant growth and development. Essential plant nutrients include phosphorus, nitrogen, potassium and sulfur. Plants require other elements such as molybdenum, in smaller quantities. Some elements e.g. aluminium and manganese, are toxic to plants.

Nutrients become available to plants when they are dissolved in water. Plants are able to take up phosphate, nitrate, potassium and sulfate ions in solution.

The solubility of nitients changes with pH. In acid soils (low pH), molybdenum becomes less soluble and aluminium becomes more soluble. Therefore, plant growth may be affected by either a deficiency of molybdenum or too much aluminium.

Both crop and pasture plants are affected by acid soils. There may be a range of symptoms. Crops and pastures may be poorly established resulting in patchy and uneven growth. Plant leaves may go yellow and die at the tips. The root system of the plant may be stunted. Crops may yield less.

Plants vary in their sensitivity to low pH. Canola and lucerne are very sensitive to acid soils so do not grow well. Lupins and triticale are tolerant to soils of low pH so they still perform well.

Land can become unproductive if acid soil is left untreated. Incorporating lime into the soil raises the pH. Therefore, liming soil can reverse the effects of acid soil on plants and return a paddock to productivity. 

Venus Eclipse

On May 16, 2010, people in most regions in the world have seen a very rare natural phenomenon. It was Venus eclipse. It was very rare amazing natural event. It was reported that the Venus eclipse will seen again in the future in 2050. Do you know how this rare Venus eclipse happens?

Well, actually Venus eclipse is like Sun eclipse. Venus eclipses occurs when the position of the earth, moon and Venus is parallel. Venus planet will slowly disappear for a moment because it is covered the surface of the Moon. Venus planet seems to move to the back side of the Moon.

The moon and planets are sharing a similar apparent path in the sky. That is why, it is not unusual for the moon to appear to pass close to Venus. In fact, the moon appears somewhere near it about once a month. However, most people don’t see these events because they are visible in the evening sky only half the time, and then only for a short period after sunset. The apparent closeness varies from month to month as well.

The Process of Rain

Water in the earth is kept in many places like the ocean, the ocean, the river and the lake. But don’t be wrong, the plants leaves and the land also kept water. Each day, this water will evaporate with help of the sun. The process where water evaporates from plants is called transpiration. Afterwards the vapors will experience the process of condensation where the vapors will condense and turn into a cloud. The form of the cloud always changes according to weather conditions. The clouds will move to different locations with the help of wind that bellows vertically or horizontally. The movement of the vertical wind results in the cloud forming big 'lumps’. After that, the wind increases the size of the cloud and each cloud will overlap. Finally the cloud will reach the atmosphere that has a lower temperature. Here the particles of water and ice are formed. Eventually, the wind can not support the weight of the cloud and so the cloud that is full with water will experience a process called precipitation or the process where rain or hail falls to earth.

   

Why Summer Daylight is longer than Winter Daylight

In the summer, the amount of daylight that we get is more than we get in winter. This is not because as much people think we are closer to the sun but because of the tilt of the earth. The earth is actually closer to the sun in winter than it is in summer but you would be forgiven for thinking that this can not be true after looking out of your window on a cold and frosty morning. It seems strange that as the earth get closer to the sun during its orbit then the amount of daylight that we get decrease. But that is the case. It is the tilt of the earth that determine the amount of daylight that we get and so the length of time that for us the sun is above the horizon