Earth And Life Science PDF

EARTH AND LIFE SCIENCE Big Bang Theory postulates that 13.8 billion years ago, the universe expanded from a tiny, dense and hot mass to its present size and much cooler state. Steady State Theory - is the PERFECT COSMOLOGICAL PRINCIPLE. The Sun is a massive, nea...

EARTH AND LIFE SCIENCE Big Bang Theory postulates that 13.8 billion years ago, the universe expanded from a tiny, dense and hot mass to its present size and much cooler state. Steady State Theory - is the PERFECT COSMOLOGICAL PRINCIPLE. The Sun is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion. Lesson 2: Earth's Subsystem Geosphere - the part of Earth that includes all the rocks, minerals, and landforms, and the ground beneath our feet. Biosphere - includes all living things on Earth, such as plants, animals, and even tiny microorganisms. Hydrosphere - includes all the water on earth. Atmosphere - the layer of gases surrounding Earth. Lesson 3: Earth's Internal Structure Crust - the earth's outermost layer. Mantle - made of molten iron and minerals that flow under pressure. Outer Core - is liquid with a thickness of about 2,400 km. Inner Core - at the centre of the earth, it's about 5500°C. Lesson 4: Minerals Minerals - naturally occurring, inorganic, homogeneous solid, with definite chemical composition and crystalline structure. Mineralogy - the study of all aspects of minerals. Properties of Minerals Color - results from impurities and geologic processes. Streak - color of mineral in powdered form. Hardness - resistance to scratch. Cleavage - lines of weakness in minerals' structure. Crystalline Structure - a unique arrangement of atoms in a mineral's crystal. Diaphaneity - ability to allow light to pass through. Luster - how light is reflected off a surface. Tenacity - describes how minerals react to stress or force. Lesson 5: Rocks Igneous Rock - formed from the hardening and crystallization of magma or molten minerals. Sedimentary Rock - formed from pre-existing rocks or pieces of once-living organisms. Metamorphic Rock - formed from pre-existing rocks modified by heat, pressure, and chemical processes. Lesson 6: Exogenic Processes Weathering - breaking down of rocks into smaller particles. Erosion - transportation of rocks from one place to another. Mass Wasting - the movement of sediments downslope under gravity. Deposition - the process where weathered materials settle in a location.