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2	Table of Contents Nature of Science Structures and Properties of Matter Forces and Motion Life Sciences Earth and Space Systems
3	Scientific Method Scientific Inquiry – Scientists ask questions about what they observe in the natural world. Inquiry guides research. Theory – A possible explanation of observations and data, which is tested and revised. Experiments – Tests a hypothesis in a controlled setting by changing a variable to see how it effects another variable.
4	Scientific Method Steps Question or Problem Research Hypothesis Experiment Analyze data Conclusion Application and Expansion
5	Important Terms
6	Terms
7	Variables Constant/Controlled variable- variable that remains the same in the experiment; doesn’t change Variable- anything can be changed Review the Scientific Method
8	Use the Scientific Method to Explain this Diagram
9	Laboratory and Field Experiments
10	Atoms and Subatomic Particles
11	Atomic Model Electron Cloud Model (click picture to review)
12	Atomic Notation
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14	Elements and Compounds
15	Chemical Reactions
16	Chemical Reactions Conservation of Mass – Mass cannot be created or destroyed in a chemical reaction Review Chemical Reactions Vision Learning Review Chemistry Concepts
17	Physical and Chemical Properties Every substance (element/compound) has a unique set of properties that allow scientists to tell it apart from other substances. Physical Property – A substance’s color, odor, density, melting point and boiling point, ductility, and conductivity
18	Physical and Chemical Properties Chemical Property – Ability of a substance to react with other substances Review Physical and Chemical Changes
19	States of Matter Solid – Have a definite volume and shape; particles vibrate in place Liquid – Have volume but no definite shape; particles flow past each other Gas – No definite volume and no definite shape; particles move independently in high speeds and in all directions Plasma – Occurs in extremely high temperatures Examples: stars, lightning, neon lights Review States of Matter
20	Periodic Table of Elements Table of elements arranged by their atomic number. An element’s position on the table will show many of its general properties Groups – Members of the same group have similar chemical and physical properties Periods – Change gradually from left to right
21	Compounds, Mixtures, Solutions Compounds – made of 2 or more elements chemically combined Mixture – 2 or more substances mixed together without chemically combining; can be separated without a chemical reaction Solution – a mixture in which one substance is dissolved uniformly in another substance Review Solutions, Mixtures, Compounds
22	Elements Metals – Hard, shiny elements appearing on the left side of the Periodic Table; good conductors of heat and electricity; Examples: Fe, Al, Na Metalloids – Appear along the bolded line on the Periodic Table; conduct electricity under some conditions; Examples: B, Si Nonmetals – Appear to the right of the Periodic Table; poor conductors of electricity; many are gases or brittle solids; Examples: C, O, S
23	Elements Noble Gas – Appear to the far right of the Periodic Table; do not combine with other substances; Examples: Ar, Ne Review Periodic Table
24	Motion Distance – Total length moved by an object Speed – Average distance traveled b a moving object in a unit of time, such as m/sec or mph Speed = distance/time Acceleration – Change in the motion of an object
25	Force Force – Push or pull causes an object to change its motion; measured in newtons Amount of force needed to change the motion of a body is proportional to the body’s mass and speed of change F= ma Balanced vs. Unbalanced forces – balanced forces have no effect on an object’s motion. A force or group of forces that push more on one side tan the other is “unbalanced” and causes a change in movement.
26	Lever Lever – Allows a force applied on the loner side of the lever to create a greater force on the shorter side of the lever Work = force X distance
27	Pulleys Pulley - Can change the direction of a force; multiple pulleys allow a person to pull a rope and raise a weight a shorter distance than the rope is pulled; this increases the amount of force
28	Wedge Wedge - an object with at least one slanting side ending in a sharp edge, which cuts material apart
29	Inclined Plane
30	Screw Screw - An inclined plane wrapped around a pole which holds things together or lifts materials.
31	Wheel and Axle A wheel with a rod, called an axle, through its center lifts or moves loads.
32	Forms of Energy Energy – the ability to do work Kinetic energy – energy of motion based on the mass and speed of the moving object Heat energy – kinetic energy based on the vibrations and movements of atoms and molecules Potential energy – stored energy; energy of position Chemical bonds- form of potential energy
33	Transformation of Energy Energy can change from one form to another Kinetic energy can turn into potential energy and back again Heat energy can be used to create electrical energy; can be converted to heat energy Law of Conservation – energy can change its form, but its total quantity is always conserved
34	Other Forms of Energy Electricity – created by movement of electrons Nuclear Energy – when large nuclei split apart, they release energy; small amounts of matter can be converted to huge quantities of energy; when joined together, the nuclei of smaller atoms can also release nuclear energy
35	Waves Mechanical waves – seismic, water, or sound waves – pass through a medium; particles of the medium pass along the energy of the wave Electromagnetic radiation – these types of wave can pass through some forms of matter but do not require it; they can also pass through a vacuum or outer space; includes invisible waves and visible light
36	Cell Theory The cell is the basic unit of all living things. All living things are made up of one or more cells. All living cells come from the reproduction of pre-existing cells.
37	Cell Structures Cells have organelles to carry out cell functions Cell membrane – supports cell; controls substances going in and out of the cell Cytoplasm – jellylike fluid in cell Nucleus – cell boss; controls cell activities
38	Animal Cell Diagram click picture to study structures
39	Plant Cell Diagram click picture to study structures
40	Cell Functions Homeostasis – a cell must maintain stable internal conditions; balance Osmosis – movement of water through a selectively permeable membrane from a higher to lower concentration Diffusion – random movement of molecules from a higher to lower concentration Turgor pressure – pressure of water against a plant cell wall Mitosis – division of the nucleus of a cell
41	How Cells Gain and Release Energy All organisms use energy to carry out the functions of life Photosynthesis – plants use light to convert carbon dioxide and water into glucose and oxygen; energy is stored in chemical bonds of glucose molecules Cellular respiration – cells break down glucose into usable energy; the reverse of photosynthesis
42	Can You Identify the Phases Mitosis? Interactive Mitosis
43	Systems Tissue – similar cells with specialized functions Organs – two or more tissues performing a function Organ System – group of organs working together to perform a specific function Organism – any living thing Feedback mechanism- occurs when the body senses the results of its actions and adjust what it is doing, allowing the body to maintain stable conditions
44	Interactions of Human Systems Muscular, Skeletal, Nervous – interact to move an arm Respiratory, Circulatory – interact to take in oxygen and deliver it to cells throughout the body Digestive and Circulatory System – interact to digest food and absorb and distribute nutrients Feedback mechanism – endocrine system interacts with other systems to maintain the body’s equilibrium, such as the level of glucose in blood
45	Organ Systems of Human Body In the human body, 10 major organ systems each work to meet a specific need: Skeletal System- support, structure, allow movement, produce red blood cells Muscular System – allows movement; smooth, skeletal, and cardiac muscles Digestive System – digests and absorbs nutrients Respiratory System: Made up of lungs and other organs that allow us to obtain oxygen Circulatory System: The heart, veins, arteries and capillaries circulate blood through the body.
46	Organ Systems of the Human Body Nervous System: The brain, sensory organs and nerves allow us to think, see, feet, and react to the environment around us. Endocrine System: Produces hormones regulating growth, fluids, blood sugar, and energy levels. Excretory System: Kidneys and bladder act as the body’s “garbage collector” to filter blood and excrete wastes and water. Integumentary system: The skin, hair and fingernails protect the body against infection and injury. Reproduction System: Organs that allow humans to produce children.
47	Heredity Inherited Trait: A trait an organism inherits from its parents, such as height or eye color. Gene: The part of a chromosome that governs a particular trait. Punnett Square: Diagram used to predict outcomes of genetic combinations. Dominant Trait: Appears if it inherits the gene for that trait from either parent; shown by capital letters on a Punnett Square. Recessive Trait: Appears only if it inherits that trait from both parents; shown by lower case letters on a Punnett Square.
48	Punnett Square Punnett Square Review Interactive Punnett Squares
49	Adaptation Genetic Mutation: Change in gene caused bu environmental damage or random error. Environmental Change: When the environment changes, such as the climate becoming colder or dryer Natural Selection: Organisms with favorable hereditary traits are more likely to survive and reproduce than other organisms; these organisms gradually increase their proportion of a species. Species: Group of similar organisms that can have children together. Population: All the members of a species living in an area.
50	Ecosystems an ecosystem is a community of living organisms and their environment in a specific area. Nonliving Environmental Factors: Non-living factors influence an ecosystem, such as temperatures, sunlight, and soil. Community: All the organisms found in a single ecosystem. Population: All of the organisms of the same species in a particular ecosystem. Examples of Land Ecosystems: Temperate forest, tropical rain forest, grassland, desert, and tundra.
51	Flow of Resources in an Ecosystem Interaction of Organisms: Predators, parasites, competition and cooperation. Recycling of Energy and Nutrients: 1. Producers (plants) obtain energy from sunlight, water and nitrates from soil. 2. Consumers (animals) eat plants or other animals; provided nitrates and CO₂ to be used by plants. 3. Decomposers (bacteria, fungi) break down dead organisms into organic compounds. Ecological Succession: Drastic events, like fire, bring a series of changes to an ecosystem.
52	Ecosystems Animal Adaptations
53	Succession Succession is the gradual and orderly process of change in an ecosystem brought about by the progressive replacement of one community by another until a stable climax is established. Succession occurs differently in different places around the world.
54	Primary Succession The process of succession that begins in a place without any soil. It starts with the arrival of living things called pioneer species - these are organisms that do not need soil to survive. Soil begins to form as the pioneer species and the forces of weather and erosion help break down rocks into smaller pieces.
55	Primary Succession When the pioneer species die, they decay, adding small amounts of organic matter to the rock; making soil. Plants such as mosses and ferns can grow in this new soil. Eventually, these plants die, adding more organic material. The soil layer thickens, and grasses, wildflowers, and other plants begin to take over.
56	Primary Succession When these plants die, they add more nutrients to the soil. This buildup is enough to support the growth of shrubs and trees. All the while, insects, small birds, and mammals have begun to move in. What was once bare rock now supports all sorts of life.
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58	Secondary Succession Secondary succession is the changes which take place in a placed that has been disturbed or damaged. Volcanoes Forest fires Development Secondary succession is usually much quicker than primary succession.
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60	Succession
61	The Movement of Earth Gravity: Gravity is a force of attraction between any two objects. Gravity governs the movements of the planets, moons, asteroids and comets in our solar system. Earth’s Movements: Earth rotates on its axis, causing day and night. 1. Earth revolves around the Sun. 2. The tilt of the Earth’s axis explains the change of seasons as Earth revolves around the Sun.
62	Stars and Phases of the Moon Stars: Scientists believe stars were formed out of clouds of gases and dust in space known as nebula. Stars produce energy through nuclear fusion, converting hydrogen into helium. Stars create all elements besides the lighter gases. Lunar Phases: The appearance of the Sun’s reflected rays on the moon and the moon's position in its orbit around Earth are responsible for the various phases of the moon.
63	Space Review Moon Phases Types of Galaxies
64	What Causes Seasons? The seasons are caused by a combination of things: The Earth is tilted as it moves around the sun. Direct sunlight produces more heat than indirect light. The Earth revolves around the sun. The difference in the amount of sunlight reaching the ground in the different hemispheres is what causes the seasons.
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66	Equinoxes
67	Seasons
68	Seasons
69	Earth’s Land Features Tectonic Plates: These are pieces of the Earth’s crust and the rock below, about 100 Km thick, that slowly move on the Earth’s surface. Their movements can create mountains, seafloor spreading, earthquakes and volcanoes. Plate Tectonic Review Weathering: wearing down of rock by wind, water, ice and living organisms. Erosion: When rock or soil is broken down into pebbles, sand of dust and transported away. Land Subsidence: When part of the Earth’s surface weakens and sinks
70	Continental Drift
71	Layers of the Earth (click picture to review)
72	Layers of the Atmosphere click on picture to review
73	Earth’s Cycles Cycles can be analyzed and predicted. Rock Cycle: Rocks move from igneous to sedimentary to metamorphic and back again. Water Cycle: Water evaporates from the ocean and other surfaces. Water then condenses into clouds and later falls back to the ground as precipitation. Ground and surface water collect in a watershed and drain off into the ocean. Carbon and Nitrogen Cycles: Involve living things: for example, plants create organic compounds; animals eat plants; carbon is released from their remains, wastes and respiration.
74	Carbon Cycle click the picture to review more
75	Nitrogen Cycle (click picture to review)
76	Rock Cycle (click picture to review)
77	Water Cycle (click picture to review)
78	The Interaction of Earth’s Systems Earth’s Systems: Earth’s systems often interact. For example, solar energy and water from the oceans interact with the atmosphere to create weather patterns. Influence of Disastrous Events: Catastrophic events, like a meteor crash, can lead to the extinction of an entire species. An endangered species is protected by government agencies because it is close to extinction.
79	Impact of Humans on Earth’s Systems Environmental problems: Global Warming: Burning of fossil fuels has increased carbon dioxide in the air. Ozone Layer: Absorbs much of the Sun’s ultraviolet radiation, but is being destroyed by CFSs. Pesticides: Pesticides can poison water, soil and the food we eat. Acid Rain: Air pollutants turn into acids that are highly toxic Loss of Non-Renewable Resources Destruction of Natural Habitats
80	Environmental Problems (click pictures to review)
81	Weathering and Erosion Weathering is the breakdown and alteration of rocks and minerals at or near the Earth's surface.
82	Weathering and Erosion Erosion is the wearing away of land or soil by the action of wind, water, or ice.
83	Types of Weathering Physical or mechanical weathering Ice wedging - water expands when it freezes and breaks apart rocks
84	Types of Weathering Physical or mechanical weathering Exfoliation - caused by expansion of rock due to uplift and erosion; rock breaks off into sheets along joints which parallel the ground surface (called sheeting).
85	Types of Weathering Physical or mechanical weathering Thermal expansion - repeated daily heating and cooling of rock; heat causes expansion; cooling causes contraction.
86	Types of Weathering Chemical weathering - Rock reacts with water, gases and solutions (may be acidic); will add or remove elements from minerals.
87	Types of Weathering Biological weathering - Organisms can assist in breaking down rock into sediment or soil.
88	Weathering
89	Types of Erosion Water Erosion – Water is the most important erosional agent and erodes most commonly as running water in streams. However, water in all its forms is erosional. Raindrops (especially in dry environments) create splash erosion that moves tiny particles of soil. Water collecting on the surface of the soil collects as it moves towards tiny rivulets and streams and creates sheet erosion
90	Types of Erosion Glaciers (frozen water) can cause erosion - they pluck and abrade. Plucking takes place by water entering cracks under the glacier, freezing, and breaking off pieces of rock that are then transported by the glacier. Abrasion cuts into the rock under the glacier, scooping rock up like a bulldozer and smoothing and polishing the rock surface
91	Types of Erosion Wind Erosion – Erosion by wind is known as aeolian erosion (named after Aeolus, the Greek god of winds) and usually occurs in deserts. Aeolian erosion of sand in the desert is partially responsible for the formation of sand dunes. The power of the wind erodes rock and sand.
92	Types of Erosion Wave Erosion – Waves in oceans cause coastal erosion. The energy of the waves along with the chemical content of the water is what erodes the rock and sand of the coastline.
93	Erosion
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