MIND MAP SCIENCE YEAR 6

Read More

MIND MAP SCIENCE YEAR 5

Read More

MIND MAP SCIENCE YEAR 4

Read More

WAJA SCIENCE PROGRAM 2009

YEAR 4 WAJA SCIENCE Theme 1 ( Investigating Living Things ) Theme 2 ( Investigating Force & Energy ) Theme 3 ( Investigating Materials ) Theme 4 ( Investigating The Earth & The Universe ) Theme 5 ( Investigating Technology ) Answers Waja Year 4 Download Waja Year 4 All ! YEAR 5 WAJA SCIENCE Theme 1 ( Investigating Living Things ) Theme 2 ( Investigating Force & Energy ) Theme 3 ( Investigating Materials ) Theme 4 ( Investigating The Earth & The Universe ) Theme 5 ( Investigating Technology ) Answers Waja Year 5 Download Waja Year 5 All ! YEAR 6 WAJA SCIENCE Theme 1 ( Investigating Living Things ) Theme 2 ( Investigating Force & Energy ) Theme 3 ( Investigating Materials ) Theme 4 ( Investigating The Earth & The Universe ) Theme 5 ( Investigating Technology ) Answers Waja Year 6 Download Waja Year 6 All !

Read More

WAJA SCIENCE PROGRAM 2008

SECTION A

Waja Module 1 Theme 1 (Part A)*****************Waja Module 6 Theme 2

Waja Module 2 Theme 1 (Part B)****************Waja Module 7 Theme 3

Waja Module 3 Theme 1****************Waja Module 8 Theme 3 Waja Module 4 Theme 1**************** Waja Module 9 Theme 4 Waja Module 5 Theme 2**************** Waja Module 10 Theme 5

Waja Module 6 Theme 2****************Waja answer Scheme SECTION B

Section B ( Variables )**********Section ( Conclusion ) Section B ( Hypothesis )************Section B ( Relationship ) Section B ( Aim)*************Section B ( Trend ) Section B ( Predicting ) Section B ( Making Inference) Download All !

Click! To Download

Read More

THE MOON

The Moon is Earth's only natural satellite and the fifth largest satellite in the Solar System. The average centre-to-centre distance from the Earth to the Moon is 384,403 km, about thirty times the diameter of the Earth. The common centre of mass of the system (the barycentre) is located about 1,700 km—a quarter the Earth's radius—beneath the surface of the Earth. The Moon makes a complete orbit around the Earth every 27.3 days (the orbital period), and the periodic variations in the geometry of the Earth–Moon–Sun system are responsible for the lunar phases that repeat every 29.5 days (the synodic period). The Moon's diameter is 3,474 km, a little more than a quarter of that of the Earth. Thus, the Moon's surface area is less than a tenth that of the Earth (about a quarter the Earth's land area, approximately as large as Russia, Canada, and the United States combined), and its volume is about 2 percent that of Earth. The pull of gravity at its surface is about 17 percent of that at the Earth's surface. The Moon is the only celestial body to which humans have traveled and upon which humans have performed a manned landing. The first artificial object to pass near the Moon was the Soviet Union's Luna 1, the first artificial object to impact the lunar surface was Luna 2, and the first photographs of the normally occluded far side of the Moon were made by Luna 3, all in 1959. The first spacecraft to perform a successful lunar soft landing was Luna 9, and the first unmanned vehicle to orbit the Moon was Luna 10, both in 1966. The United States (U.S.) Apollo program achieved the only manned missions to date, resulting in six landings between 1969 and 1972. Human exploration of the Moon ceased with the conclusion of the Apollo program, although a few robotic landers and orbiters have been sent to the Moon since that time. Nonetheless, several countries have announced plans to return humans to the surface of the Moon in the 2020. Phases Of Moon

The Moon makes a complete orbit around the Earth with respect to the fixed stars about once every 27.3 days (its sidereal period). However, since the Earth is moving in its orbit about the Sun at the same time, it takes slightly longer for the Moon to show its same phase to Earth, which is about 29.5 days (its synodic period). Unlike most satellites of other planets, the Moon orbits near the ecliptic and not the Earth's equatorial plane. It is the largest moon in the solar system relative to the size of its planet. (Charon is larger relative to the dwarf planet Pluto.) The natural satellites orbiting other planets are called "moons", after Earth's Moon. Most of the tidal effects seen on the Earth are caused by the Moon's gravitational pull, with the Sun making a somewhat smaller contribution. Tidal drag slows the Earth's rotation by about 0.002 seconds per day per century. As a result of the conservation of angular momentum, the slowing of Earth's rotation is accompanied by an increase of the mean Earth-Moon distance of about 3.8 m per century, or 3.8 cm per year. The Moon is exceptionally large relative to the Earth, being a quarter the diameter of the planet and 1/81 its mass. However, the Earth and Moon are still commonly considered a planet-satellite system, rather than a double-planet system, since the common centre of mass of the system (the barycentre) is located about 1,700 km beneath the surface of the Earth, or about a quarter of the Earth's radius. The surface of the Moon is less than one-tenth that of the Earth and only about a quarter the size of the Earth's land area (or about as large as Russia, Canada, and the U.S. combined). Eclipse Of The Moon

Eclipses can occur only when the Sun, Earth, and Moon are all in a straight line. Solar eclipses occur near a new moon, when the Moon is between the Sun and Earth. In contrast, lunar eclipses occur near a full moon, when the Earth is between the Sun and Moon. Because the Moon's orbit around the Earth is inclined by about 5° with respect to the orbit of the Earth around the Sun, eclipses do not occur at every full and new moon. For an eclipse to occur, the Moon must be near the intersection of the two orbital planes. The periodicity and recurrence of eclipses of the Sun by the Moon, and of the Moon by the Earth, is described by the saros cycle, which has a period of approximately 6 585.3 days (18 years 11 days 8 hours). The angular diameters of the Moon and the Sun as seen from Earth overlap in their variation, so that both total and annular solar eclipses are possible. In a total eclipse, the Moon completely covers the disc of the Sun and the solar corona becomes visible to the naked eye. Since the distance between the Moon and the Earth is very slightly increasing over time, the angular diameter of the Moon is decreasing. This means that hundreds of millions of years ago the Moon could always completely cover the Sun on solar eclipses so that no annular eclipses were possible. Likewise, about 600 million years from now (assuming that the angular diameter of the Sun will not change), the Moon will no longer cover the Sun completely and only annular eclipses will occur.

Read More

SCIENCE SECTION B GUIDE

Tips & Tricks 1. You are given 30 minutes. 2. Questions are based on diagram / pictures/bar charts/dialogues/statements. 3. Read the question carefully and understand it. The information given can guide you to answer the question. 4. Your answers should be short and brief. 5. Your handwriting should be neat and easy to read. 6. Differentiate the three variables. 7. Check your answers and make sure that your spelling are correct and use the correct science terms.

1. Observation Use all the five senses to tell about some things • smell • taste • texture • size • Condition Maria’s duck Danial’s duck State an observation from the diagram. A) Maria’s duck is bigger than Daniel's duck. B) Maria’s duck is heavier than Daniel's duck. 2. Inference To reach a decision by thinking or reasoning. Reason For Observation State one inference from your observation. a) Maria fed her duck with nutritious food than Daniel’s duck. b) The quantity of food given to Maria’s duck is more than Daniel’s duck. c) Maria’s duck gene is better then Daniel’s duck. 3. Controlling data 3.1 Constant variable/fixed variable Things that are kept the same Example : the same • size of beaker /glass/box/room/plant… • distance • type of plant/ball/liquid/flower/duck… • quantity of fruits/sugar/salt… • volume/amount of water 3.2 Manipulated variable Things that are changed Example : the different • type of materials/plant/liquid… • size of books/room /balloon.. • quantity of sugar/salt/ • volume of water/liquid/coffee… • distance or • the presence of water/air/sunlight 3.3 Controlling Variables Make sure that each variable is answered in a complete sentence. comparison measurement (characteristic) of + object higher/lower ............................................temperature water larger/bigger ............................................volume oil/box heavier/lighter..........................................mass iron ball/fruits larger/smaller ..........................................shape container more /less .................................................numbers ball/fruits/marbles more/less ..................................................time taken for the ice cubes to melt longer /shorter .........................................length string/rope darker/brighter ........................................colour material / shirt /container thicker/thinner..........................................thickness cloth/book larger/bigger..............................................size box/cup/plate further/nearer...........................................distance toy car to stop 3.3 Responding variable The result of the experiment Example : • condition of materials/plants/rats after… • the number of…. • time taken to … 3.4 State the following variables : i – manipulated variable : the quantity of food the quality of food the gene of duck ii – responding variable : the size of the duck the weight of the duck iii – controlled variables : the type of ducks 4. The aim of an investigation a) To investigate the relationship between MV and RV b) To study the relationship between MV and RV 4.1 What is the aim of the investigation? i) To investigate the relationship between the quantity of food given to the duck and the size of the duck. ii) To investigate the relationship between the quality of food given to the duck and the weight of the duck. 5. Hypothesis An idea or suggestion, put forward as a starting-point for reasoning or an explanation. An early idea that must be tested. The more ( comparison of adverb/adjective ) MV the more (comparison of adverb/adjective) RV Write one hypothesis based on the diagram. i) The more quantity of food given to the duck the heavier the weight of duck. ii) The better the quality of food given to the duck the bigger the size of the duck. iii) The better the gene of the duck the bigger the size of the duck. 6. Conclusion What is settle in the mind. 1. On the whole – plants/animals/humans/object etc 2. According to the question What conclusion can be made from this investigation? i) Ducks need high quality of food to grow bigger in size. ii) Ducks with better gene will grow bigger. ii) Ducks that are given more quantity of food will have heavier weight. Maria and Daniel rear ten ducks in the same size coop. The result are recorded for three month. 7. Predicting Expecting what will happen based on the observation/ information/data/prior knowledge. If the question ask for specific numbers that can be calculate, you have to give a specific numbers. Example 1 : Predict the weight of Maria’s duck after four month. ……………………………………………………… If the question is in the statement form /incomplete data Example 2 : Predict the weight of Maria’s ducks on the forth month if the quantity of food are reduce to one kilogram per day. …………………………………………………………………………………… SCIENCE PROCESS SKILL IN SECTION B

1. OBSERVING 2. INFERENCING 3. PREDECTING 4. INTERPRETING DATA 5. VARIABLE 6. HYPOTHESIS CRITERIA IN SECTION B

1. OBSERVATION 2. INFERENCE 3. PREDICTING 4. TREND 5. RELATIONSHIP 6. CONCLUSION 7. MANIPULATED VARIABLE (WHAT TO CHANGE) 8. RESPONDING VARIABLE (WHAT TO MEASURE) 9. CONTROLLED VARIABLE (KEPT TO SAME) 10. AIM 11. HYPOTHESIS Question 1 The picture shows a torchlight .The table shows the ability of the torch light using three batteries to function at different times. Time(hours)......Brightness of the bulb in torch light 2.......................Brightest 4.......................Bright 6.......................Dim 1. Based on the experiment, state the following variables: What to change/ manipulated :………………………………………………………. What to measure/ responding :…………………………………………………………. Kept the same/ controlled : …………………………………………………………. 2. What is the aim of the investigation? …………………………………………………………………………………………………… 3. Suggest one hypothesis based on the table. ………………………………………………………………………………………………………… 4. What is your observation about the brightness of the bulb for two hours? ………………………………………………………………………………………………………… 5 . State your inference based on your observation. ………………………………………………………………………………………………………… 6. What is your conclusion based on the table? ……………………………………………………………………………………………………… ……………………………………………………………………………………………………… Suggested Answers 1. Based on the experiment, state the following variables: What to change/ manipulated : time What to measure/ responding : Brightness of the bulb in torch light Kept the same/ controlled : type of battery, number of battery

2. To study/ investigate the relationship between the time and the brightest of the bulb in torch light. 3. The more the time the more the brightest of the bulb in torch light / if the time increase then the brightest of the bulb in torch light decrease. 4. The brightest of the bulb in torch light is more brightest at two hour. 5. The brightest of the bulb in torch light is more brightest at two hour because there is enough power.

6. The more the time the more the brightest of the bulb in torch light / if the time increase then the brightest of the bulb in torch light decrease.

Source: SK Sayung, Kuala Kangsar.

Read More

PLANET PLUTO

Click Play Button To Start The Video

Pluto is the second-largest known dwarf planet in the Solar System and the tenth-largest body observed directly orbiting the Sun. Originally classified as a planet, Pluto is now considered the largest member of a distinct population called the Kuiper belt. Like other members of the Kuiper belt, Pluto is composed primarily of rock and ice and is relatively small: approximately a fifth the mass of the Earth's Moon and a third its volume. It has an eccentric and highly inclined orbit that takes it from 30 to 49 AU (4.4–7.4 billion km) from the Sun. This causes Pluto periodically to come closer to the Sun than Neptune. Pluto and its largest moon, Charon, are sometimes treated together as a binary system because the barycentre of their orbits does not lie within either body. The International Astronomical Union (IAU) has yet to formalise a definition for binary dwarf planets, and until it passes such a ruling, Charon is classified as a moon of Pluto. Pluto has two known smaller moons, Nix and Hydra, discovered in 2005. Like Uranus, Pluto rotates on its "side" relative to its orbital plane, and the Pluto-Charon system does also. From its discovery in 1930 until 2006, Pluto was considered the Solar System's ninth planet. In the late 1970s, following the discovery of minor planet 2060 Chiron in the outer Solar System and the recognition of Pluto's very low mass, its status as a major planet began to be questioned. Later, in the early 21st century, many objects similar to Pluto were discovered in the outer solar system, notably the scattered disc object Eris, which is 27% more massive than Pluto. On August 24, 2006, the IAU defined the term "planet" for the first time. This definition excluded Pluto as a planet, and added it as a member of the new category "dwarf planet" along with Eris and Ceres. After the reclassification, Pluto was added to the list of minor planets and given the number 134340. A number of scientists continue to hold that Pluto should be classified as a planet.

Read More

PLANET URANUS

Click Play Button To start The Video

Uranus is the seventh planet from the Sun, the third-largest, and the fourth most massive planet in the Solar System. Though it is visible to the naked eye like the five classical planets, it was never recognized as a planet by ancient observers because of its dimness and slow orbit. Sir William Herschel announced its discovery on March 13, 1781, expanding the known boundaries of the solar system for the first time in modern history. This was also the first discovery of a planet made using a telescope. Uranus is similar in composition to Neptune, and both have different compositions from those of the larger gas giants Jupiter and Saturn. As such, astronomers sometimes place them in a separate category, the "ice giants". Uranus's atmosphere, while similar to Jupiter's and Saturn's in being composed primarily of hydrogen and helium, contains a higher proportion of "ices" such as water, ammonia and methane, along with traces of hydrocarbons. It is the coldest planetary atmosphere in the Solar System, with a minimum temperature of 49 K (−224 °C). It has a complex, layered cloud structure, with water thought to make up the lowest clouds, and methane thought to make up the uppermost layer of clouds. In contrast the interior of Uranus is mainly composed of ices and rock. Like the other giant planets, Uranus has a ring system, a magnetosphere, and numerous moons. The Uranian system has a unique configuration among the planets because its axis of rotation is tilted sideways, nearly into the plane of its revolution about the Sun. As such, its north and south poles lie where most other planets have their equators. Seen from Earth, Uranus's rings can sometimes appear to circle the planet like an archery target and its moons revolve around it like the hands of a clock, though in 2007 and 2008 the rings appeared edge-on. In 1986, images from Voyager 2 showed Uranus as a virtually featureless planet in visible light without the cloud bands or storms associated with the other giants. However, terrestrial observers have seen signs of seasonal change and increased weather activity in recent years as Uranus approached its equinox. The wind speeds on Uranus can reach 250 meters per second (900 km/h, 560 mph).

Read More

PLANET NEPTUNE

Click Play Button To Start The Button

Neptune is the eighth planet from the Sun in the Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third-largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 Earth masses and not as dense. On average, Neptune orbits the Sun at a distance of 30.1 AU, approximately 30 times the Earth-Sun distance. Discovered on September 23, 1846, Neptune was the first planet found by mathematical prediction rather than by empirical observation. Unexpected changes in the orbit of Uranus led astronomers to deduce that its orbit was subject to gravitational perturbation by an unknown planet. Neptune was subsequently found within a degree of its predicted position, and its largest moon, Triton, was discovered shortly thereafter, though none of the planet's remaining 12 moons was located telescopically until the 20th century. Neptune has been visited by only one spacecraft, Voyager 2, which flew by the planet on August 25, 1989. Neptune is similar in composition to Uranus, and both have compositions which differ from those of the larger gas giants Jupiter and Saturn. Neptune's atmosphere, while similar to Jupiter's and Saturn's in that it is composed primarily of hydrogen and helium, along with traces of hydrocarbons and possibly nitrogen, contains a higher proportion of "ices" such as water, ammonia and methane. Astronomers sometimes categorize Uranus and Neptune as "ice giants" in order to emphasize these distinctions. The interior of Neptune, like that of Uranus, is primarily composed of ices and rock. Traces of methane in the outermost regions in part account for the planet's blue appearance.

Read More

PLANET SATURN

Saturn

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn, along with Jupiter, Uranus and Neptune, is classified as a gas giant. Together, these four planets are sometimes referred to as the Jovian, meaning "Jupiter-like", planets. The planet Saturn is composed of hydrogen, with small proportions of helium and trace elements. The interior consists of a small core of rock and ice, surrounded by a thick layer of metallic hydrogen and a gaseous outer layer. The outer atmosphere is generally bland in appearance, although long-lived features can appear. Wind speeds on Saturn can reach 1,800 km/h, significantly faster than those on Jupiter. Saturn has a planetary magnetic field intermediate in strength between that of Earth and the more powerful field around Jupiter.

comparison of the sizes of Saturn and Earth

Saturn has a prominent system of rings, consisting mostly of ice particles with a smaller amount of rocky debris and dust. Sixty-one known moons orbit the planet, not counting hundreds of "moonlets" within the rings. Titan, Saturn's largest and the Solar System's second largest moon (after Jupiter's Ganymede), is larger than the planet Mercury and is the only moon in the Solar System to possess a significant atmosphere.

Read More

PLANET JUPITER

Click Play Button To Start The Video

Jupiter, pronounced is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass slightly less than one-thousandth that of the Sun but is two and a half times more massive than all of the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn, Uranus and Neptune. Together, these four planets are sometimes referred to as the Jovian planets. The planet was known by astronomers of ancient times and was associated with the mythology and religious beliefs of many cultures. The Romans named the planet after the Roman god Jupiter. When viewed from Earth, Jupiter can reach an apparent magnitude of −2.8, making it on average the third-brightest object in the night sky after the Moon and Venus. (Mars can briefly exceed Jupiter's brightness at certain points in its orbit.) Jupiter is primarily composed of hydrogen with a quarter of its mass being helium; it may also have a rocky core of heavier elements. Because of its rapid rotation, Jupiter's shape is that of an oblate spheroid (it possesses a slight but noticeable bulge around the equator). The outer atmosphere is visibly segregated into several bands at different latitudes, resulting in turbulence and storms along their interacting boundaries. A prominent result is the Great Red Spot, a giant storm that is known to have existed since at least the 17th century when it was first seen by telescope. Surrounding the planet is a faint planetary ring system and a powerful magnetosphere. There are also at least 63 moons, including the four large moons called the Galilean moons that were first discovered by Galileo Galilei in 1610. Ganymede, the largest of these moons, has a diameter greater than that of the planet Mercury.

Read More

PLANET MARS

Click Play Button To Start The Video

Mars is the fourth planet from the Sun in the Solar System. The planet is named after Mars, the Roman god of war. It is also referred to as the "Red Planet" because of its reddish appearance, due to iron oxide prevalent on its surface.

Size comparison of Earth and Mars.

Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts and polar ice caps of Earth. It is the site of Olympus Mons, the highest known mountain in the Solar System, and of Valles Marineris, the largest canyon.

Mars

Furthermore, in June 2008 three articles published in Nature presented evidence of an enormous impact crater in Mars' northern hemisphere, 10,600 km long by 8,500 km wide, or roughly four times larger than the largest impact crater yet discovered, the South Pole-Aitken basin. In addition to its geographical features, Mars’ rotational period and seasonal cycles are likewise similar to those of Earth.

Mar's Surface

Until the first flyby of Mars by Mariner 4 in 1965, many speculated that there might be liquid water on the planet's surface. This was based on observations of periodic variations in light and dark patches, particularly in the polar latitudes, which looked like seas and continents, while long, dark striations were interpreted by some observers as irrigation channels for liquid water.

Mar's Surface

These straight line features were later proven not to exist and were instead explained as optical illusions. Still, of all the planets in the Solar System other than Earth, Mars is the most likely to harbor liquid water, and perhaps life. Radar data from Mars Express and the Mars Reconnaissance Orbiter have revealed the presence of large quantities of water ice both at the poles (July 2005) and at mid-latitudes (November 2008). The Phoenix Mars Lander directly sampled water ice in shallow Martian soil on July 31, 2008.

Read More

PLANET EARTH

Famous "Blue Marble" photograph of Earth, taken from Apollo 17

Earth is the third planet from the Sun, and the largest of the terrestrial planets in the Solar System in terms of diameter, mass and density. It is also referred to as the World, Blue Planet, and Terra.

Size comparison of inner planets (left to right): Mercury, Venus, Earth and Mars

Home to millions of species, including humans, Earth is the only place in the universe where life is known to exist. The planet formed 4.54 billion years ago, and life appeared on its surface within a billion years. Since then, Earth's biosphere has significantly altered the atmosphere and other a biotic conditions on the planet, enabling the proliferation of aerobic organisms as well as the formation of the ozone layer which, together with Earth's magnetic field, blocks harmful radiation, permitting life on land.

Earth cutaway from core to exosphere

The physical properties of the Earth, as well as its geological history and orbit, allowed life to persist during this period. The world is expected to continue supporting life for another 1.5 billion years, after which the rising luminosity of the Sun will eliminate the biosphere.Earth's outer surface is divided into several rigid segments, or tectonic plates, that gradually migrate across the surface over periods of many millions of years. About 71% of the surface is covered with salt-water oceans, the remainder consisting of continents and islands; liquid water, necessary for all known life, is not known to exist on any other planet's surface. Earth's interior remains active, with a thick layer of relatively solid mantle, a liquid outer core that generates a magnetic field, and a solid iron inner core.

Read More

PLANET VENUS

Venus is the second-closest planet to the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love. Except for the Moon it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6. Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°. Venus reaches its maximum brightness shortly before sunrise or shortly after sunset, for which reason it is often called the Morning Star or the Evening Star. Classified as a terrestrial planet, it is sometimes called Earth's "sister planet," because they are similar in size, gravity, and bulk composition. Venus is covered with an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light.

Venus is always brighter than the brightest stars

Venus has the densest atmosphere of all the terrestrial planets, consisting mostly of carbon dioxide, as it has no carbon cycle to lock carbon back into rocks and surface features, nor organic life to absorb it in biomass.

Impact craters on the surface of Venus

A younger Venus is believed to have possessed Earth-like oceans, but these totally evaporated as the temperature rose, leaving a dusty dry deserts cape with many slab-like rocks. The water has most likely dissociated, and, because of the lack of a planetary magnetic field, the hydrogen has been swept into interplanetary space by the solar wind. The atmospheric pressure at the planet's surface is 92 times that of the Earth.

Read More

YEAR 5 DOWNLOADS

Tropical Questions Chapter 1 ( Microorganism )*********Chapter 2 ( Survival ) Chapter 3 ( Food Chain & Web)*********Chapter 4 ( Energy) Chapter 5 ( Electricity)*********Chapter 6 ( Light) Chapter 7 ( Heat)*************Chapter 8 ( State of Matter ) Chapter 9 ( Acid & Alkaline)**********Chapter 10 ( Constellation ) Chapter 11 (The Earth )***********Chapter 12 ( Stability) Download All ! Click ! To Download.

Read More

PLANET MERCURY

Click! To Play The Video

Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about the axis for every two orbits. The perihelion of Mercury's orbit processes around the Sun at an excess of 43 arc seconds per century; a phenomenon that was explained in the 20th century by Albert Einstein's General Theory of Relativity. Mercury is bright when viewed from Earth, ranging from −2.0 to 5.5 in apparent magnitude, but is not easily seen as its greatest angular separation from the Sun is only 28.3°. Since Mercury is normally lost in the glare of the Sun, unless there is a solar eclipse, Mercury can only be viewed in morning or evening twilight.

Read More

THE SUN

Click! to Play the Video

The Sun is the star at the center of the Solar System. The Earth and other matter (including other planets, asteroids, meteoroids, comets, and dust) orbit the Sun, which by itself accounts for about 98.6% of the Solar System's mass. The mean distance of the Sun from the Earth is approximately 149,598,000 kilometers (92,956,000 mi), and its light travels this distance in 8 minutes and 19 seconds. But it varies throughout the year from a minimum of 147,100,000 kilometers (91,400,000 mi) on 3 January, to a maximum of 152,100,000 kilometers (94,500,000 mi) on 4 July. Energy from the Sun, in the form of sunlight, supports almost all life on Earth via photosynthesis, and drives the Earth's climate and weather. The surface of the Sun consists of hydrogen (about 74% of its mass, or 92% of its volume), helium (about 24% of mass, 7% of volume), and trace quantities of other elements, including iron, nickel, oxygen, silicon, sulfur, magnesium, carbon, neon, calcium, and chromium. The Sun has a spectral class of G2V. G2 means that it has a surface temperature of approximately 5,780 K (5,500 °C) giving it a white color that often, because of atmospheric scattering, appears yellow when seen from the surface of the Earth. This is a subtractive effect, as the preferential scattering of shorter wavelength light removes enough violet and blue light, leaving a range of frequencies that is perceived by the human eye as yellow. It is this scattering of light at the blue end of the spectrum that gives the surrounding sky its color. When the Sun is low in the sky, even more light is scattered so that the Sun appears orange or even red.

Read More

YEAR 4 DOWNLOADS

Tropical Questions

Chapter 1 ( Basic Needs )******Chapter 2 ( Life Processes ) Chapter 3 ( Protection )*******Chapter 4 ( Measurement ) Chapter 5 ( Properties Of Material) Chapter 6 ( The Solar System )********** Chapter 7 ( Technology ) Download All ! Click ! To Download

Read More

EXTINCT ANIMALS

A species becomes extinct when the last existing member of that species dies. Extinction therefore becomes a certainty when there are no surviving individuals that are able to reproduce and create a new generation. A species may become functionally extinct when only a handful of individuals survive, which are unable to reproduce due to poor health, age, sparse distribution over a large range, a lack of individuals of both sexes (in sexually reproducing species), or other reasons. Pinpointing the extinction (or pseudo extinction) of a species requires a clear definition of that species. If it is to be declared extinct, the species in question must be uniquely identifiable from any ancestor or daughter species, or from other closely related species. Extinction of a species (or replacement by a daughter species) plays a key role in the punctuated equilibrium hypothesis of Stephen Jay Gould and Niles Eldredge. In ecology, extinction is often used informally to refer to local extinction, in which a species ceases to exist in the chosen area of study, but still exists elsewhere. This phenomenon is also known as extirpation. Local extinctions may be followed by a replacement of the species taken from other locations; wolf reintroduction is an example of this. Species which are not extinct are termed extant. Those that are extant but threatened by extinction are referred to as threatened or endangered species. An important aspect of extinction at the present time are human attempts to preserve critically endangered species, which is reflected by the creation of the conservation status "Extinct in the Wild" (EW). Species listed under this status by the World Conservation Union (IUCN) are not known to have any living specimens in the wild, and are maintained only in zoos or other artificial environments. Some of these species are functionally extinct, as they are no longer part of their natural habitat and it is unlikely the species will ever be restored to the wild. When possible, modern zoological institutions attempt to maintain a viable population for species preservation and possible future reintroduction to the wild through use of carefully planned breeding programs. The extinction of one species' wild population can have knock-on effects, causing further extinctions. These are also called "chains of extinction".

Passenger Pigeon

The earliest settlers in the New World were amazed by the passenger pigeon, a bird with flocks so huge that it would take days for them to travel overhead, blackening the sky as they passed. Any farmer who had the misfortune of hosting passenger pigeons for a meal would quickly find his entire crop decimated within the blink of an eye. Then, virtually overnight, the most abundant bird in North America suddenly disappeared from the planet. The extinction of the passenger pigeon is an example of nature coming into direct conflict with man. Its population numbered an astounding 3 to 5 billion when the first Europeans arrived in America. However, there was not room enough in the New World for both species. Passenger pigeons were soon wiped out due to merciless hunting, deforestation and other factors related to humankind's ever-expanding range. The extinction was only becoming apparent at the start of the 20th century; by 1914, the last known bird was dead.

Quagga The quagga is a mammal closely related to modern horses and zebras. In fact, it looks like a cross between a horse and a zebra, with stripes only on its head and neck that disappear as they approach the brownish hindquarters of the animal. The quagga was native to desert areas of South Africa until it was hunted to extinction in the 1870s. The last captive animals died in Europe in the 1880s. As an extinct species, the quagga has a couple claims to fame. For starters, it was the first animal to have its DNA analyzed, which led to the discovery that the quagga was not a distinct species but a subspecies of the plains zebra. Also, the quagga is the subject of an ambitious breeding effort by the aptly named Quagga Project, the result of which was a foal born in 2005. Based on appearances, the "re-created" quagga closely resembles the ancient quagga, but DNA evidence has yet to determine whether this animal is authentic.

Archaeopteryx

Holding the No.8 spot in our countdown is an ancient creature named Archaeopteryx, whose discovery in the mid-1800s turned the world of paleontology upside down. It looked like some sort of feathered dinosaur, but it also had a number of bird characteristics. Was it a bird, a dinosaur or some other beast entirely? Clues would come in time, but only after decades of contentious debate and close examination. In order to fully understand the natural history of Archaeopteryx, one needs first to take a look at some of its unusual characteristics. Its dinosaur features include a full set of teeth, a flat breastbone, a bone tail and claws on the end of its wing. On the other hand, its feathers and wings also made it quite birdlike. However, details of Archaeopteryx anatomy indicated that it was not ideally built for flight and probably spent as much time running, leaping, climbing and gliding as it did flying.

Saber-Toothed Cat

Of all the cute, cuddly animals found in the fossil record, the saber-toothed cat (also called the saber-toothed tiger) is one of the last you would want to meet in a dark alley. With their daggerlike canine teeth and powerful bodies, this animal was one of the most ferocious predators of the Cenozoic Period. It lived in North America and Europe and went extinct about 10,000 years ago. There have been several thousand saber-toothed cat specimens found at the famous La Brea Tar Pits in Los Angeles, Calif. – so many that it was named the state fossil of California.

So, what were these big beasts like in the wild? Evidence suggests that the saber-toothed cat had a social structure much like modern lions, living together and cooperating in order to bring down prey.

Interestingly, researchers also believe that a certain amount of nurturing went on in a saber-toothed cat pack. Many individual fossils show signs of extensive regeneration and healing after disease and injury, suggesting an environment in which individuals could be cared for by other members of the group. Despite their terrifying appearance, it seems these animals had a soft side.

The Dodo Bird Contrary to popular belief, the dodo was not a stupid or lazy bird. After all, it lived in a predator-free environment where food was plentiful on the ground. Why bother flying when you can simply stroll about at a leisurely pace? But what was by all accounts the sweet life for the dodo came to an abrupt end in the1600s, when European explorers landed on Mauritius, the island in the Indian Ocean where the dodo made its home. After their arrival, it would be only a few short years before the animal was hunted to extinction, primarily because it was a much-needed source of meat for weary sailors. In addition, the pigs, dogs and rats that inevitably accompanied sailing ships made short work of dodo eggs, which were all too accessible from their nests on the ground. The dodo never stood a chance. Mammoth If there is one animal most associated with the Ice Age, it has to be the woolly mammoth, that giant shaggy beast with long ivory tusks curling up from its massive trunk-like nose. The woolly mammoth was one of several species of mammoth, the earliest of which were probably small and amphibious creatures living in North Africa until about three million years ago. Their descendants eventually dispersed throughout Eurasia and the woolly mammoth, one of the smaller mammoth species, migrated to North America across the Bering Land Bridge sometime during late Pleistocene. Alas, this enigmatic creature did not survive long in the New World. The last of the woolly mammoths died out at the end of the last ice age, about ten thousand years ago. Thylacine-Tasmanian Tiger The Thylacine the largest known carnivorous marsupial of modern times. Native to continental Australia, Tasmania and New Guinea, it is thought to have become extinct in the 20th century. It is commonly known as the Tasmanian Tiger (because of its striped back), the Tasmanian Wolf, and colloquially the Tassie (or Tazzy) Tiger or simply the Tiger. It was the last extant member of its genus, Thylacinus, although several related species have been found in the fossil record dating back to the early Miocene.

The Thylacine became extinct on the Australian mainland thousands of years before European settlement of the continent, but it survived on the island of Tasmania along with several other endemic species, including the Tasmanian Devil. Intensive hunting encouraged by bounties is generally blamed for its extinction, but other contributory factors may have been disease, the introduction of dogs, and human encroachment into its habitat. Despite its official classification as extinct, sightings are still reported. Like the tigers and wolves of the Northern Hemisphere, from which it obtained two of its common names, the Thylacine was an apex predator. As a marsupial, it was not related to these placental mammals, but because of convergent evolution it displayed the same general form and adaptations. Its closest living relative is thought to be either the Tasmanian Devil or Numbat.

Read More

Endangered Fish

It's hard to say how fish are faring as a whole, as only 10 percent of the nearly 30,000 known fish species have been evaluated for inclusion in the IUCN Red List of Threatened Species. Tellingly, nearly half those surveyed are now considered threatened or endangered. Overfishing is likely the leading cause of fish declines, followed closely by habitat loss and pollution. Some of the most unique fish species in the world are facing imminent extinction, including the ancient coelacanth and the bizarre smalltooth sawfish.

COELACANTH (Latimeria chalumnae)

The coelacanth is referred to as a living fossil because it is the only remaining species of a group of fish species that died out millions of years ago. It is found in the deep coastal waters of eastern Africa, where rocky shores are battered by strong oceanic currents. It is a large fish, growing to a length of about 6 feet, and it moves along the rocky slopes with the help of fleshy pectoral fins. Populations of this species are thought to be critically low.

IUCN Status: Critically Endangered

Major Threat: Accidental capture by fishing operations

Habitat: Volcanic and rocky slopes in deep coastal waters

Location: Eastern Africa

Diet: Cuttlefish, squid, snipe eels, small sharks and other fish

LOST RIVER SUCKER (Deltistes luxatus)

The Lost River sucker is a large fish found in the freshwater ecosystems of California and Oregon. It is a long-lived fish, sometimes reaching an age of 40 years or more. Its primary home is in lakes, but it migrates to rivers and streams to breed. The Lost River sucker is threatened by overfishing and by the damming of rivers and the draining of wetlands.

IUCN Status: Endangered

USFWS Status: Endangered

Major Threats: Overfishing, damming of rivers and draining of wetlands

Habitat: Lakes, rivers and streams

Location: California and Oregon

Diet: Mainly detritus; also midge larvae, amphipods and zooplankton

MEKONG GIANT CATFISH (Pangasianodon gigas) The Mekong giant catfish is a freshwater fish that grows to be very large — about as large as a grizzly bear in some cases. This enormous fish was historically found throughout the Mekong River, which is the 12th longest river in the world. The waterway spans about 2,983 miles (4,800 kilometers) from its headwaters in the Tibetan Plateau throughout much of Southeast Asia. Currently, Mekong giant catfish populations are in rapid decline, primarily due to dams, overfishing and pollution.

IUCN Status: Critically Endangered

Major Threats: Dams, overfishing and pollution

Habitat: Rivers

Location: Lower half of the Mekong River

Diet: Aquatic plants and algae

NASSAU GROUPER (Epinephelus striatus)

The Nassau grouper is a large, predatory coral reef fish that is found in the western Atlantic Ocean, Florida Keys, Gulf of Mexico and Caribbean Sea. It has a habit of visiting cleaning stations on coral reefs, where wrasse fish pick parasites out of its mouth and gills. It also camouflages itself in order to ambush prey. The Nassau grouper is in serious decline due to fishing and loss of coral reef habitat.

IUCN Status: Endangered

Major Threat: Fishing and habitat loss

Habitat: Coral reefs

Location: Western Atlantic Ocean, Florida Keys, Gulf of Mexico and Caribbean Sea

Diet: Mainly other fish and crabs

RUSSIAN STURGEON (Acipenser gueldenstaedtii)

The Russian sturgeon is a large, bony fish that can reach a length of more than 6 feet. It lives in salt water and travels upriver to spawn, which makes it vulnerable to habitat loss on multiple fronts, including hydroelectric dams that create barriers to spawning grounds, pollution in both its freshwater and saltwater homes, and being heavily fished for its meat and eggs, which are used to make caviar.

IUCN Status: Endangered

Major Threat: Overfishing, pollution and habitat loss

Habitat: Seas and large rivers

Location: Black Sea, Caspian Sea and adjacent river systems

Diet: Mainly mollusks

SMALLTOOTH SAWFISH (Pristis pectinata)

Like sharks, skates and rays, sawfish have skeletons made of cartilage rather than bone. The smalltooth sawfish is a long, sleek fish that occurs in shallow coastal and estuarine waters in the Atlantic and Pacific oceans as well as the Gulf of Mexico. It also has a long, flattened snout lined with rows of teeth that it uses to locate and subdue prey. In addition to facing the threat of hunting, pollution and habitat loss, it is extremely vulnerable to being caught in fishing lines. IUCN Status: Critically Endangered

USFWS Status: Endangered

Major Threats: Hunting, pollution, habitat loss and being caught in fishing lines

Habitat: Shallow coastal and estuarine waters

Location: Altantic and Pacific oceans and the Gulf of Mexico

Diet: Mainly fish and some crustaceans

Read More

Endangered Birds

Birds of every shape, size and color are under threat. From the mighty California condor to the tiny purple-backed sunbeam, birds around the world are running out of time. And space — habitat loss is the single largest threat facing birds today. Ironically, bird enthusiasts themselves are also helping to contribute to the decline of many species, which are captured for the caged bird trade. Of the nearly 10,000 described bird species, over 1,200 are listed as threatened or endangered by the IUCN. Some are facing seemingly hopeless battles, while others are recovering from decades of decline. The future hangs in the balance for many of our feathered friends.

BLACK-CAPPED VIREO (Vireo atricapilla)

The black-capped vireo is a tiny songbird that lives in the oak woodlands of Texas, Oklahoma and Northern Mexico. It has a brownish body, a black cap, red eyes and white "spectacles" formed by rings around the eyes. Once abundant, this species is now endangered due to agricultural expansion and other human activities. It is also threatened by nest parasites such as the brown-headed cowbird that invade the vireo's nest, knock out the eggs, and replace them with its own.

USFWS Status: Endangered

Major Threats: Habitat loss due to agricultural expansion; nest parasites

Habitat: Oak woodlands

Location: Texas, Oklahoma and Northern Mexico

Diet: Insects, primarily caterpillars and beetles,

BROWN KIWI (Apteryx mantelli)

The brown kiwi is a stocky nocturnal bird that is native to New Zealand. A flightless bird, the brown kiwi feeds by walking slowly through the forest poking its long, slender bill — which is highly sensitive to touch — into the ground in search of worms, insects and larvae. It was once found throughout New Zealand, but is now restricted to fragmented forests and seriously threatened by non-native predators such as pigs, cats and dogs. IUCN Status: Endangered

Major Threat: Non-native predators such as pigs, cats and dogs Habitat: Temperate, tropical and subtropical forest and scrubland Location: New Zealand Diet: Worms, insects and larvae CALIFORNIA CONDOR (Gymnogyps californianus)

California condors are large vultures with bald pink heads and a 10-foot wingspan. They are among the world's largest flying birds, and they are also one of the most critically endangered. After going extinct in the wild due to hunting, habitat loss and environmental poisons, captive breeding programs have allowed for the reintroduction of a small population of California condors into the wild. There are currently populations in California, Arizona, and Baja California, Mexico. IUCN Status: Critically Endangered USFWS Status: Endangered Major Threats: Hunting, habitat loss and environmental poisons Habitat: Wooded mountains and scrublands Location: California, Arizona, and Baja California, Mexico Diet: Carrion, especially larger animals like deer, cattle and sheep CROWNED EAGLE (Harpyhaliaetus coronatus)

The crowned eagle is a mighty bird of prey with broad wings, pale gray plumage and a distinct crest on its head. It occurs throughout central South America in both forest and semi-open areas. Like many birds of prey, the crowned eagle is endangered because of habitat loss. As top predators, they are also vulnerable to toxins present in their prey animals, and are subject to harassment by humans who perceive them as a threat to farm animals.

IUCN Status: Endangered Major Threats: Habitat loss, persecution and toxins present in prey animals Habitat: Open woodland, marshland, savanna and scrub Location: Central South America Diet: Birds, medium-sized mammals and reptiles

YELLOW-EARED PARROT (Ognorhynchus icterotis)

The yellow-eared parrot is critically endangered because of its extremely small range and shrinking habitat due to deforestation. It is bright green with yellow ear patches and a dark, heavy bill. This breathtakingly beautiful bird is also a popular species in the exotic pet trade. It is currently only thought to occur among the wax palms in the cloud forests of the Colombian Andes.

Read More