6 th Grade Science SOL Review Packet

Transcription

1 6 th Grade Science SOL Review Packet The information in this packet is for your reference as we review for the SOL. Do not lose it! 6.3 Role of Solar Energy The Earth's energy budget The Earth receives only a very small portion of the sun s energy, yet this energy is responsible for powering the motion of the atmosphere, the oceans, and many processes at the Earth s surface. Solar radiation is made up of different types of radiation including infrared, visible light, and ultraviolet. (Know terms wavelength; ultraviolet, visible, and infrared radiation; and reflection and absorption.) Incoming solar radiation is in close balance with the energy that leaves the atmosphere; otherwise the Earth would heat up or cool down. (Analyze and interpret a chart or diagram showing the Earth s energy budget.) Excess carbon dioxide and other gases may disrupt this balance, creating a Greenhouse Effect. (Explain the Greenhouse Effect in terms of the energy entering and leaving the atmosphere.) About one third of the sun s incoming energy is reflected back out to space. About one half of the energy striking the Earth is absorbed by the Earth s surface. Radiation and convection distribute heat energy around the globe The Earth s surface is heated unequally. When air or water is heated, the molecules move faster and farther apart, reducing their density, causing them to rise. Cooler air or water molecules move more slowly and are denser than warm air or water. Warm air or water rising coupled with cooler air or water descending forms a cyclic rising/falling pattern called convection. Radiation and convection from the surface transfer heat energy. This energy powers the global circulation of the atmosphere and the oceans on our planet. (Students should analyze and explain how convection currents occur, and how they distribute heat energy in the atmosphere and oceans.) 1. The sun s energy contributes to powering the motion of the, the oceans, and other processes at the Earth s. 2. What types of radiation is solar radiation made of? 3. Earth s energy budget explains that incoming energy from the sun is in with energy that leaves the atmosphere. 4. What type of gas contributes to the greenhouse effect? 5. Explain how convection occurs on the Earth for air and water. 6.5 Properties of Water Water's Role in Physical and Chemical Weathering Water (rain, ice, snow) has shaped our environment by physically and chemically weathering rock and soil and transporting sediments. Freezing water can break rock without any change in the minerals that form the rock (physical weathering). This usually produces small particles and sand. Water with dissolved gases and other chemicals causes the minerals in rocks to be changed, leading to the deterioration of the rock (chemical weathering). Examples of chemical weathering: acidified water on building material such as concrete, limestone, or marble causes chemical weathering.

2 1. What is it called when water changes the environment physically and chemically? 2. Explain three types of weathering that occur from water. a. Freezing water - b. Water with dissolved gases - c. Acidified water Earth s Atmosphere Air is a Mixture Air is a mixture of gaseous elements and compounds. These include nitrogen, oxygen, water, argon and carbon dioxide. Nitrogen makes up the largest proportion of the air. Air exerts pressure. Air pressure decreases with altitude. Moisture in the air is called humidity. The Atmosphere The atmosphere is made up of layers (troposphere, stratosphere, mesosphere, and thermosphere) that have distinct characteristics. Temperature decreases with altitude in the lowest layer of the atmosphere. Most of the air that makes up the atmosphere is found in the troposphere, the lowest layer. Virtually all weather takes place there. Forest fires and volcanic eruptions are two natural processes that affect the Earth's atmosphere. Many gaseous compounds and particles are released into the atmosphere by human activity. All of the effects of these materials are not yet fully understood. Weather The amount of heat energy, water vapor, and the pressure of the air largely determine what the weather conditions are. (Measure and record air temperature, air pressure, and humidity in using appropriate units of measurement and tools.) Weather maps show much useful information about descriptive air measurements, observations, and boundaries between air masses (fronts). The curved lines showing areas of equal air pressure and temperature are key features of weather maps. Weather maps are important for understanding and predicting the weather. (Interpret charts and graphs of the atmosphere in terms of temperature and pressure; relate temperature, barometric pressure, and humidity to changing weather conditions; interpret basic weather maps, and make forecasts based on the information presented; map the movement of cold and warm fronts, and interpret their effects on observable weather conditions.) Clouds are important indicators of atmospheric conditions. Clouds are found at various levels within the troposphere. Three major types of clouds are cumulus, stratus, and cirrus clouds. (Compare and contrast cloud types, and relate cloud types to weather conditions; compare and contrast types of precipitation and weather-related phenomena including thunderstorms, tornados, hurricanes, and drought.) Ozone, a form of oxygen, can form near the surface when exhaust pollutants react with sunlight. This pollutant can cause health problems. Naturally occurring ozone is also found in the upper atmosphere and helps to shield the Earth from ultraviolet radiation. Maintaining good air quality is a crucial goal for modern society, and it is everyone's responsibility to work toward it. 1. What types of gases make up air? 2. How are air pressure and altitude related? 3. What are the layers of the atmosphere? 4. What types of natural processes affect the Earth s atmosphere? Why? 5. What determines the weather conditions? 6. Explain how weather maps show useful information between fronts.

3 7. What are some types of clouds? 8. What is the effect of ozone? 6.7 Watersheds The concepts developed in this standard include the following: An ECOSYSTEM is made up of the living community and the non-living factors that affect it. The health of an ecosystem is directly related to water quality. ABIOTIC FACTORS determine ecosystem type, its distribution of plants and animals as well as the usage of land by people. Abiotic factors include water supply, topography, landforms, geology, soils, sunlight, and air quality/o2 availability. HUMAN ACTIVITIES can alter abiotic components and thus accelerate or decelerate natural processes. For example, people can affect the rate of erosion (a natural process). Plowing cropland can cause erosion, while planting trees can prevent it. (riparian buffer) Flood protection/wetland loss is another example.(explain the factors that affect water quality in a watershed and how those factors can affect an ecosystem) A WATERSHED is the land that water flows across or through on its way to a stream, lake, or wetland. Areas of higher elevations, such as ridgelines or divides, separate watersheds. The THREE MAJOR REGIONAL WATERSHEDS SYSTEMS in Virginia lead to the Chesapeake Bay, the North Carolina sounds, and the Gulf of Mexico RIVER SYSTEMS are made up of tributaries of smaller streams that join along their courses. Rivers and streams generally have wide flat, border areas, called flood plains, onto which water spills out at times of high flow WETLANDS form the transition zone between dry land and bodies of water such as rivers, lakes, or bays. Both TIDAL and NON-TIDAL WETLANDS perform important water quality functions including regulating runoff by storing flood waters; reducing erosion by slowing down runoff; maintaining water quality by filtering sediments, trapping nutrients and breaking down pollutants; and recharging groundwater. They also provide food and shelter for wildlife and fish and nesting and resting areas for migratory birds. The CHESAPEAKE BAY is an estuary where fresh and salt water meet and are mixed by tides. It is the largest estuary in the contiguous United States and one of the most productive. ESTUARIES perform important functions, such as providing habitat for many organisms and serving as nurseries for their young. WATER QUALITY MONITORING is the collection of water samples to analyze chemical and/or biological parameters. Simple parameters include ph, temperature, salinity, dissolved oxygen, turbidity, and the presence of macro-invertebrate organisms. 1. What is a watershed? 2. Explain river systems. 3. What are wetlands? 4. Why are wetlands important? 5. What do estuaries do? 6.8 Solar System - The solar system consists of the sun, moon, Earth, other planets and their moons, meteors, asteroids, and comets. Each body has its own characteristics and features. - The distance between planets and sizes of the planets varies greatly. The outer, gas planets are very large, and the four inner planets are comparatively small and rocky.

4 Observe the relative sizes of the planets. Mercury is the smallest, Saturn and Jupiter the largest. Asteroids are like tiny planets. There are about 2000 of them orbiting around the sun, mostly on a path between Mars and Jupiter. Meteors are chunks of matter orbiting the sun in orbits that cross the planets. When meteors occasionally hit the Earth's atmosphere, they vaporize and give off a streak of light. Comets are balls of ice and rock circling the sun from regions beyond Pluto. Glowing clouds surround most comets, and tails of gas can often be seen trailing them as their orbits take them near the sun. The Earth is a geologically active planet with a surface that is constantly changing. Unlike the other four inner planets, it has large amounts of life-supporting water and an oxygen-rich atmosphere. The Earth s protective atmosphere blocks out most of the sun s damaging rays. The Earth is one of eight planets that revolve around the Sun and comprise the solar system. The Earth, third planet from the sun, is one of the four rocky inner planets. It is about 150 million kilometers from the sun. Remember the order of the planets with the sentence: My Very Educated Mother Just Served Us Nachos. Gravity is a force that keeps the planets in motion around the sun. Gravity acts everywhere in the universe. Planets revolve around the sun, and moons revolve around planets. A planet rotates upon an axis. As the Earth rotates, different sides of the Earth face toward or away from the sun, thus causing day and night, respectively. Rotation or Revolution? Rotation and Revolution: Planets revolve around the sun, and moons revolve around planets. A planet rotates upon an axis. The Earth completes one revolution (or orbit) around the sun every year (365 days). The Earth completes one rotation on its axis every 24 hours. Day and Night -As the Earth rotates, different sides of the Earth face toward or away from the sun causing day and night. The phases of the moon are caused by its position relative to the Earth and sun. The Moon's Phases The moon revolves around the Earth every days. The phases of the moon are caused by the moon's position relative to the Earth and the sun. (we see only part of the sunlit side of the moon) The phases of the moon include the new, waxing crescent, first quarter, waxing gibbous, full, waning gibbous, last quarter, and waning crescent. Waxing (Light is on the Right) Waning (Light is on the left) The Earth is a rocky planet, extensively covered with large oceans of liquid water, and having frozen ice caps in its polar regions. The Earth has a protective atmosphere consisting predominantly of nitrogen and oxygen and has a magnetic field. The

5 atmosphere and the magnetic field help shield the Earth s surface from harmful solar radiation. Scientific evidence indicates that the Earth is about 4.5 billion years old. Seasons are caused by the tilt of the Earth on its axis, and thus, the angle at which sunlight strikes the surface of the Earth during its annual revolution around the sun. Earth's Tilt and the Seasons Earth's tilt causes seasons: The Earth is tilted on its axis as it revolves around the sun. The hemisphere tilted toward the sun receives the sun's rays more directly and therefore has warmer temperatures as well as longer days (summer), while the half of the Earth tilted away has cooler temperatures and shorter days (winter). It's important to realize that warmer summer temperatures occur because the Sun's rays are striking more directly, not because part of the Earth is closer to the Sun. Tides are the result of the gravitational pull of the moon and sun on the surface waters of the Earth. Tides -Tides are the result of the gravitational pull of the moon on the waters of the Earth. The moon's gravity causes the oceans to bulge at point nearest the moon, and also at the directly opposite point on the side of the Earth. The two bulges at opposite sides of the Earth is the why there are two high and two low tides every day. Twice a month, new moon and full moon, the tides are especially high because the lined up with the moon and gravity from the sun pulls the oceans These are called "spring tides." During first quarter and third quarter the tides are low because the sun and moon are pulling in opposite directions and essentially canceling each other out. surface the other reason at the sun is also. moons, The ideas of Ptolemy, Aristotle, Copernicus, and Galileo contributed to the development of our understanding of the solar system. History Our understanding of the solar system has changed from an Earth-centered model (Aristotle and Ptolemy) to the suncentered model (Copernicus and Galileo). With the expansion of technology over the last half century, our knowledge of the solar system has increased substantially. SPUTNIK 1 - Modern space exploration began in 1957 with Soviet launch of this satellite MERCURY PROGRAM - Sent the first Americans into space in 1961 PROJECT APOLLO - Landed 12 humans on the moon between 1969 and VOYAGER SPACE PROBES - Sent back pictures of Jupiter, Saturn, and Neptune. A space probe is a robot vehicle used to explore deep space. VIKING 1 AND 2 Landed on Mars in 1976 and sent back data about the planet's soil and atmosphere PIONEER PROBES - Used instruments to see through the thick clouds that cover Venus SPACE SHUTTLES - In use since 1981, the first reusable spacecraft HUBBLE SPACE TELESCOPE - Launched in 1990, it produces images five times as sharp as any telescope on Earth 1. Which planets are the smallest, and which are the largest? 2. What are the differences between asteroids, meteors, and comets?

6 3. Why is Earth so unique from other planets? 4. Write the mnemonic device (the saying that helps you remember something) for the order of the planets. Then, write the planet name underneath! 5. Why do we have day and night? 6. What is the difference between rotation and revolution? 7. Write the moon s phases in order. You may draw pictures to assist you. 8. Explain why we have different seasons. 9. How does the position and gravity of the moon affect tides? 10. Which scientists were focused on an Earth-centered model? 11. Which scientists were focused on a Sun-centered model? 6.9 Environment and Public Policy People, as well as other living organisms, are dependent upon the availability of clean water and air and a healthy environment. Local, state, and federal governments have significant roles in managing and protecting air, water, plant, and wildlife resources. Modern society is dependent upon many finite resources including coal, oil, natural gas, and nuclear power. Many renewable and nonrenewable resources are managed by the private sector (private individuals and corporations). Regulations, incentives, and voluntary efforts help conserve resources and protect environmental quality. Conservation of resources and environmental protection begin with the individual. Use of renewable and nonrenewable resources must be considered in terms of their cost/benefit tradeoffs. Preventive measures, such as pollution prevention or thoughtfully planned and enforced land-use restrictions can reduce the impact of potential problems in the future. Pollution prevention and waste management are less costly than cleanup. Renewable resources should be managed so they produce continuously. Sustainable development makes decisions about long-term use of the land and natural resources for maximum community benefits, for the longest time, with the least environmental damage.