Ecosystems

1. 4TH GRADE SCIENCE AT-A-GLANCE Ecosystems Rocks & Minerals Weathering & Erosion Electricity & Magnetism Amy Edmundson & Maureen Allen Grade Four - Science Content Standards Physical Sciences Electricity and magnetism are related effects that have many useful applications in everyday life. As a basis for understanding this concept: 1a) Design and build simple series and parallel circuits by using components such as wires, batteries, and bulbs. 1b) Build a simple compass and use it to detect magnetic effects including Earth's magnetic field. 1c) Electric currents produce magnetic fields and know how to build a simple electromagnet. 1d) The role of electromagnets in the construction of electric motors, electric generators, and simple devices, such as doorbells and earphones. 1e) Electrically charged objects attract or repel each other. 1f) Magnets have two poles (north and south) and that like poles repel each other while unlike poles attract each other. 1g) Electrical energy can be converted to heat, light, and motion. Life Sciences All organisms need energy and matter to live and grow. As a basis for understanding this concept: 2a) Plants are the primary source of matter and energy entering most food chains. 2b) Producers and consumers (herbivores, carnivores, omnivores, and decomposers) are related in food chains and food webs and may compete with each other for resources in an ecosystem. 2c) Decomposers, including many fungi, insects, and microorganisms, recycle matter from dead plants and animals. Living organisms depend on one another and on their environment for survival. As a basis for understanding this concept: 3a) Ecosystems can be characterized by their living and nonliving components. 3b) In any particular environment, some kinds of plants and animals survive well, some survive less well, and some cannot survive at all. 3c) Many plants depend on animals for pollination and seed dispersal, and animals depend on plants for food and shelter. 3d) Most microorganisms do not cause disease and that many are beneficial. Earth Sciences The properties of rocks and minerals reflect the processes that formed them. As a basis for understanding this concept: 4a) Differentiate among igneous, sedimentary, and metamorphic rocks by referring to their properties and methods of formation (the rock cycle). 4b) Identify common rock-forming minerals (including quartz, calcite, feldspar, mica, and hornblende) and ore minerals by using a table of diagnostic properties. Waves, wind, water, and ice shape and reshape Earth's land surface. As a basis for understanding this concept: 5a) Some changes in the earth are due to slow processes, such as erosion, and some are due to rapid processes, such as landslides, volcanic eruptions, and earthquakes. 5b) Natural processes, including freezing and thawing and the growth of roots, cause rocks to break down into smaller pieces. 5c) Moving water erodes landforms, reshaping the land by taking it away from some places and depositing it as pebbles, sand, silt, and mud in other places (weathering, transport, and deposition).

2. A compass is a device that contains a magnetized needle that moves freely and is used to detect a magnet or magnetic field. The north end of the compass needle seeks (points towards) the Earth’s magnetic north pole. If a compass is near a magnet or magnetic field, it will point in that direction. An electromagnet is a device that turns an iron nail or bolt into a magnet by wrapping an insulated wire that has an electric current running through it around the nail or bolt. The electric current running through the wire causes it to become a “temporary magnet” with a North and South Pole because the magnetic field causes the atoms in the bolt to line up in a North/South direction, just like a real magnet. It can be turned on and off. Electric motors, door bells, speakers, and earphones are all examples of electromagnets. What happens when you increase the number of winds /coils around a bolt in an electromagnet? ______________________________________________________________________________________________________ PS 1b, 1c, 1d 14 Notes: 1

3. ATTRACT REPEL LIFE SCIENCE MAGNETS Ecosystems have living (biotic) and non-living (abiotic) components. Magnets have two poles (north and south). Like poles repel each other and unlike poles attract each other. In any environment, some plants and animals can survive WELL….can survive LESS WELL….or DON’T survive at all! Plants depend on animals for POLLINATION and SEED DISPERSAL. A magnetic field is the space in which the force of a magnet can act. Iron filings can show the magnetic field around a bar magnet. The filings are closer together at the poles of the magnet because the magnetic force is stronger. A magnet can attract any iron, cobalt, or nickel object that comes within its magnetic field. Animals depend on plants for FOOD AND SHELTER. Most microorganisms do NOT cause disease and many are beneficial (helpful). Earth’s Magnetic Field - The Earth’s center is made up mostly of molten iron. As the Earth rotates, the iron particles line up, producing a magnetic field. The Earth behaves like a huge bar magnet with two magnetic poles. Bacteria is a microorganism. While some types of bacteria cause illness, others can be found in food such as yogurt, sour cream, and cheese. Plankton are microorganisms that live in water and produce food that is the beginning of many ocean food chains. LS 3a, 3b, 3c, 3d 2 PS 1b, 1f 13

4. Electrical Energy Converts to A producer is an organism that can produce its own food. HEAT LIGHT MOTION A consumer is an organism that gets its energy by eating plants or other organisms. An herbivore is a consumer that only eats plants. An omnivore is a consumer that eats both plants and animals. A carnivore is a consumer that eats only animals. A series circuit consists of two or more light bulbs with a battery in a single path. Any break in the circuit can stop the flow of the electricity and none of the components will work. If one light goes out, they all go out. A decomposer is an organism that breaks down dead organic matter into simple chemical compounds, thereby returning nutrients to the environment. Examples: worms, mold, fungi, bacteria. A food chain shows the path of food energy in an ecosystem from plants to animals. A parallel circuit has more than one pathway that conducts the electrical current each having their own components and path back to the battery. If there is a break in any pathway, the electricity will go through another pathway. If one light goes out, the rest stay lit. What happens when you take out one bulb in a: series circuit? Why? ___________________________________ ____________________________________________________ parallel circuit? Why?__________________________________ ____________________________________________________ Name two animals that are herbivores ______________________ LS 2a, 2b, 2c 3 PS 1a, 1g 12

5. STATIC ELECTRICITY A food web is formed when two or more food chains have the same organism in common. Static electricity occurs when a charge builds up on an object or material. An object gains or loses negative electrical charges (electrons). Electrically charged objects attract or repel each other. Like Charges Repel Objects with like charges repel each other when brought close together. The balloons have more positive (+) charges, therefore they have the “same” charge and repel each other. Unlike Charges Attract Objects with unlike charges attract each other when brought close together. The balloon has more negative (-) charges and the sock has more positive (+) charges, therefore they attract each other. What happens to the balloons after the charges are “balanced?” ___________________________________________ ___________________________________________ Circle the secondary consumers and put a box around the producers in the food chain. PS1e 11 LS 2a, 2b, 2c 4

6. WEATHERING & EROSION THE ROCK CYCLE Any type of rock can change into any other type of rock. The rock cycle shows the processes that change rocks. Weathering is the breaking and cracking of earth materials and erosion is the movement and deposition of those materials. Weathering produces boulders, cobbles, sand, silt, and clay. Erosion transports and deposits these earth materials from one place to another. Color each numbered rock face as it becomes each type of rock in the rock cycle. (1-3) Melted rock (magma) may cool and form Igneous Rocks underground, such as granite, or erupt through a crack in the Earth’s crust as a volcano. (4-5) Rocks on the surface may be weathered and eroded by water, wind, waves, and ice, into smaller rocks or sediments and transported and deposited in layers on the earth’s crust. (6-7) Over time, lithification (cementing sediments together) forms Sedimentary Rocks that become buried deep in the crust. (8) Heat and pressure from the mantle can cause any type of rock to change, re-arrange its atoms, and re-crystallize into hard, dense, Metamorphic Rocks. What is weathering? _______________________________ __________________________________________________ What is erosion? ___________________________________ __________________________________________________ ES 5c 5 ES 4a 10

7. Igneous rocks are formed above and below the earth’s surface. Magma, which is melted rock material, can cool below the earth’s surface or erupt through volcanoes and then cool on the earth’s surface. Granite Sedimentary rocks are formed at or near the earth’s surface and are weathered and broken apart (eroded) by wind, rain, or ice and deposited as sediments in rivers, lakes, and oceans. Over time the sediments are cemented together through a chemical process called “lithification.” Sandstone Metamorphic rocks are buried deep in the earth’s crust and are heated up, but not melted, from the heat and pressure in the mantel. Once heated, the rocks re-organize their atoms, cool, and re-crystallize into hard, dense, rocks. Gneiss ES 4a 9 Slow Processes Igneous, Sedimentary, and Metamorphic Rocks Some changes in the earth are due to slow processes such as: Chemical Weathering Plant Growth Wind Erosion Glacier Movement Ice Wedging Wave Action Flowing Water Rapid Processes Some changes in the earth are due to rapid processes such as: Volcanoes Landslides Earthquakes ES 5a, 5b 6

8. MINERALS Cleavage is the tendency for some minerals to split easily along flat surfaces when they are broken apart. Geologists describe and identify minerals according to their properties such as hardness, cleavage, color, and streak. The color of a mineral cannot always be used to identify it because impurities from the surrounding area can be mixed with mineral when it is forming and can turn the mineral different colors. Amethyst Quartz Smokey Quartz The luster of a mineral describes the way the surface of a mineral reflects light. Metallic minerals reflect light and nonmetallic materials do not reflect light. The streak of the mineral is the color of powder left behind when the mineral is scratched onto another mineral or on a piece of unglazed tile. Hardness is a measure of how easily a mineral may scratch or be scratched by another mineral. What mineral am I? 1) I am shiny and yellow and I have a greenish black streak. Who am I? _________________________ 2) I am silver-gray, metallic or nonmetallic. I have a reddish brown streak. Who am I? _________________________ 3) I am a big flake! I can be silver-white but I’m not shiny & I scratch easily. Who am I? _________________________ 4) I’m nonmetallic, have a white streak, and I bubble when vinegar is placed on me. Who am I? _________________________ ES 4b 8 ES 4b 7