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Science Processes and Technology:

Before starting a lab or activity study the procedure, if you have questions ask your teacher. (90% of all accidents occur due to lack of understanding of the procedure)
Use all safety equipment properly. Safety glasses are to protect your eyes, not your forehead.
Never eat or drink in the lab, never use glassware as food or drink containers. Never inhale chemicals, use wafting technique
Keep all materials away from open flames. Tie back loose hair and clothing.
Report any accident or injury, no matter how small to the teacher.
In a scientific investigation only one variable should be tested at a time.
An independent variable is the one(s) you control in the experiment, on the x axis of a graph.
The dependent variable is the one you are testing, on the y axis of a graph.
Graphs and tables are useful to show mathematical relationships between variables.
A dichotomous key is a tool to classify organisms or other specimens by characteristics.

ECOLOGY:
Populations:

A population is a group of the same species that lives in an area at the same time.
Limiting factors for populations include food supply, predators, competition, climate, and disease.
The largest size a particular population that can be supported by a particular environment is the environment’s carrying capacity.
Symbiosis is a close long term association between two or more species. There are thee types: Mutualism-both organisms benefit. Commensialism- one benefits and the other is unharmed. Parasitism- where one organism benefits while the other is harmed or killed.

Communities:

A community is a group of animal and plant populations living together in the same environment.
A community of plants and animals that covers a large geographical area is called a biome. Major biomes are deserts, forests, grasslands, tundra, and aquatic.
The boundaries of different biomes are determined mainly by climate.
Changes in communities occur over times in a process called ecological succession. Succession is a series of slow, predictable changes in the number and kinds of organisms in an area.
Primary succession is when organisms begin to inhabit an area that had no life or soil.
Secondary succession takes place after an existing community suffers a major disruption but soil is present.

Ecosystems:

Ecology is the study of the relationship between organisms and their environment. Ecologists study the organization of these relationships.
An ecosystem is made up of a community and its abiotic (non-living or physical) environment.
The six main elements of an ecosystem are the sun, other abiotic substances, producers, primary consumers, secondary consumers, and decomposers.
An abiotic substance means it is non-living. Abiotic substances include climate, soil, water, air, nutrients, and energy.
A biotic substance is a living substance. Plants, animals, fungus, bacteria, etc.
The sun is the ultimate source of energy for ecosystems.
Producers make food by the process of photosynthesis. Most producers are green plants. Plants need abiotic substances to grow.
Primary consumers are plant-eating animals. Secondary consumers, or predators, eat animals.
Decomposers break down dead plants and animals into simple nutrients.
The model that shows the series of energy changes goes through as it is passed from one organism to another is called a food chain. A food web is overlapping networks of food chains.
The energy pyramid is a model that shows how much energy passes through organisms and shows that as consumer energy needs increase, populations decrease. The energy flows from greatest to smallest: plants, herbivores, carnivores.

Cycling of materials:

Living things are made of mostly water, carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. All of those compounds are recycled endlessly and reused over and over again.
Water continuously moves from the Earth to the atmosphere and back again in a process called the water cycle. Thefive major parts of the water cycle are: precipitation, evaporation, condensation, transpiration and run-off.
Precipitation is when water falls to earth in any form: rain, snow, hail, or sleet.
Condensation is when water vapor cools and changes back into liquid droplets, forming clouds.
Evaporation is when liquid water changes into a gaseous form called water vapor.
Transpiration is when water vapor is released through opening in the plant’s leaves called stomata.
Run-off is water, usually from precipitation, flows across the land and collects in rivers, streams then eventually lakes and oceans.
The energy for the water cycle comes from the sun.
Carbon is continuously moved in various forms from the atmosphere, in organisms and substances and back again in the carbon cycle. Photosynthesis, respiration, decomposition, and combustion are important steps in the carbon cycle.
Photosynthesis is the process by which plants use carbon dioxide and water to make their own food and release oxygen.
Respiration - organisms use the food and oxygen, created during photosynthesis, for energy and turn it back into carbon dioxide and water for the plants to use for photosynthesis.
Nitrogen is continuously moved in various forms from the atmosphere, in organisms and substances and back again in the Nitrogen Cycle. Nitrogen cannot be used by plants in its natural form. Nitrogen fixation must occur for plants and animals to use it. Nitrogen is fixed by bacteria in the soil and lightning

Conservation

Conservation is making wise choices with the resources we have. Conservation methods include: reducing how much we use, reusing resources when possible and recycling products so the resources are still available to us.
Natural resources include everything not made by humans that can be used by organisms.
Renewable resources are resources that can be replaced relatively quickly such as trees and water. Non-renewable resources, such as fossil fuels, cannot be replaced relatively quickly
Fossil fuels such as coal, oil, and natural gas are from the remains of once living organisms.
Obtaining and using fossil fuels can cause many environmental problems such as water pollution acid rain and smog. Most people use fossil fuels because they are often cheaper or more convenient then the alternatives.
Habitat destruction threatens biodiversity in many ecosystems. The result is many organisms are becoming endangered or extinct.
Alternative energy sources are being developed using the sun, wind, moving water, and the heat of the earth to help minimize problems from fossil fuels.

Weather:

Weather is the state of the atmosphere at a certain place and time. Climate is the weather of a place averaged over a length of time.
A meteorologist is a person that studies the weather.
Air is a mixture of gasses and tiny particles that are 78 percent nitrogen and 21 percent oxygen.
Three key factors that determine the weather in the troposphere are air temperature, air pressure, and humidity.
The atmosphere is heated in three ways. Conduction is heating by transferring of energy through direct contact. Convection is heating by transferring energy through circulation of a liquid or gas. Most movement of energy in the atmosphere is through convection. Radiation is the heating by electromagnetic rays from the sun.
Sunlight heats the surface of the earth and this heat is trapped by the gasses of the atmosphere (like a blanket) this process known as the greenhouse effect.
Air pressure is the weight of the air pushing on you. Air pressure is, on average, highest at sea level, and lowest at high altitude.
Cold air is more dense than and it exerts higher pressure compared to warm air which is less dense and exerts lower pressure.
Regions where air pressure is relatively high usually experience fair weather. Regions where air pressure is relatively low experience cloudy, stormy weather
Wind is air moving from areas where the air pressure is relatively high toward areas where the air pressure is relatively low.
Humidity is a measure of the amount of water vapor in the air. Air that contains its maximum amount of water vapor is described as saturated.
When saturation occurs within the atmosphere water vapor condenses into droplets (or develops into tiny ice crystals) that form clouds.
The amount of water vapor the air can hold increases as the air temperature rises and decreases as the temperature falls.
Clouds usually form where air moves up and not where air moves downward.
The troposphere is the lowest layer of the atmosphere. Most weather occurs in the troposphere. It extends from the earth’s surface up to an altitude of about 6 to 10 miles. Most clouds occur here.
Stratosphere is the second level and has a fairly constant temperature.
Mesosphere is the third layer of the atmosphere.
Thermosphere is the highest and largest layer.
The exosphere is the outer most reaches of the atmosphere.
Coriolis Effect is a shift in the winds caused by a rotation in the earth.
Global winds near the earth’s surface split into three belts in each hemisphere the trade winds, the westerlies, and the polar winds.
Trade winds north of the equator blow from the northeast, trade winds south of the equator, blow from the southeast.
Westerlies blow from the southwest in the Northern Hemisphere and from the northwest in the Southern Hemisphere.
Polar easterlies blow from the northeast in the Arctic and from the southeast in the Antarctic.
Local winds are caused by geographical features such as a lake or an ocean.
Westerlies near the top of the troposphere and just over the polar front and are known as the Jet Stream.
An air mass is a huge volume of air covering thousands of square mines or kilometers that is relatively uniform in temperature and humidity. The properties of an air mass depend on where it forms. Maritime air forms over water, and is usually wet. Continental air forms over land, and is usually dry.
Across North America, warm air masses generally move north and northeastward. Cold air masses move south and southeastward.
A front is a narrow zone of transition between air masses that differ in temperature or humidity.
A cold front is the leading edge of an advancing cold air mass the cold air advances by moving under and pushing up the retreating warm fronts. Cold fronts move faster then warm fronts.
When a warm air mass rises over top of a cold air mass a warm front occurs.
A stationary front is when a warm and cold air mass collides and there is little horizontal movement. The result is generally drizzly precipitation.
An occluded front is when a two cold air masses force a warm air mass up. (a warm front and cold front collide)

Types of Clouds:

Cirrus clouds are high altitude, wispy clouds.
Stratus clouds are flat layered grey clouds that often bring a drizzle.
Cumulus clouds are thick, puffy and white with a flat bottoms.
Cumulonimbus clouds are dark towering cumulus clouds that bring lightening and heavy rain.

Measuring the Weather:

A thermometer checks air temperature.
A psychrometer measures the amount of relative humidity in the air.
A barometer shows the air pressure.
An anemometer monitors wind speed.
A rain gauge measures rainfall.

Human Impact on the weather:

The construction of cities creates areas that are drier and warmer than the surrounding country-side called a heat island.
Heat energy rising from a city also spurs the growth of clouds.
Smog is a mixture of gasses and tiny particles that reduces visibility and poses serious health problems.
Burning fossil fuels puts large amounts of carbon dioxide in the atmosphere, increasing greenhouse effect creating global warming.

Forces in Fluids:

Fluids are substances that the shape of their container, liquids and gases are fluids
Buoyancy is an upward force produced by fluids. The greater the density of the fluid, the greater the buoyant force.
Archimedes’ principle states that the buoyant force on an object is equal to the weight of the fluid the object displaces. If the object displaces its own weight of the fluid it is in it will float.
Density is the mass of an object compared to its volume. Measured in grams per milliliter.
Objects with a density greater than the fluid it is in will sink, with a lower density will float.

Energy:

Energy is something that allows a body to do work. Energy cannot be created or destroyed, it changes form (Law of conservation of energy)
Inertia is the resistance of a body to a change in its state of motion.
Kinetic Energy is the energy of motion = mass x velocity.
Potential Energy is stored energy due to position (gravitational) or changing shape (spring or bow).

Forces and Motion:

A force is a push or pull on an object that will can it’s state of motion
A Newton is the metric unit of force (weight).
When forces are applied in the same direction they are added. When forces are applied in opposite direction they are subtracted.
Forces on an object are balanced when the object is at rest or is moving at a constant rate. Unbalanced forces result in motion.
Speed is the distance something travels divided by the time it took (S= D÷T)
Friction is a force that resists motion