Life on Earth depends on three interconnected factors: The one-way flow of high quality energy sun living things (feeding interactions) environment (low quality energy) back into space as (infrared radiation - heat). Cycling of matter or nutrients through parts of the biosphere. Gravity which allows the planet to hold on to its atmosphere and causes the downward movement of chemical in the matter cycles.

Vocabulary to begin.. Abiotic – non-living Biotic – living

More Vocabulary… Levels of biological organization to know: Organism Population Community Ecosystem Biosphere

Earth’s Four Realms Hydrosphere – Earth’s supply of water liquid and frozen, fresh and salty Atmosphere – gaseous envelope surrounding the earth Lithosphere – soil and rock of Earth’s crust Biosphere – all living organisms

Let’s Practice What is the word for… A group of individuals of the same species that occupy a common area. The unique environment that organisms are best adapted to energy resources. One individual living thing. Where an organism lives. A group of organisms that are able to produce fertile offspring.

Let’s Practice What is the word for… A physically distinct, self-supporting unit of interacting organisms and their environment. Means living. A group of interacting populations of different species Means non-living.

Energy Quality is.. The measure of an energy sources’ ability to do useful work Entropy: a measure of disorder or randomness of a system

Types of Energy Quality High quality: organized or concentrated and can perform much useful work. Examples… electricity nuclear energy solar energy

Types of Energy Quality Low quality: disorganized or dispersed and has little ability to do useful work. Example… heat in the ocean

Closed vs. Open System The earth is an open system for energy. We receive energy from the sun and heat energy is released back into the universe. We exchange energy with our surroundings. The earth is a closed system for matter. Matter is never created or destroyed. All matter that is here has always been here. Are you breathing the same oxygen atoms the dinosaurs breathed???

Two Laws of Energy 1 st Law of Thermodynamics – Energy is neither created or destroyed but can be transformed from one form to another. 2 nd Law of Thermodynamics – Whenever energy is converted from one form to another, some usable energy (energy available to do work) is degraded into heat (a less usable form that disperses into the environment.) *** Because of this, the amount of usable energy available to do work decreases over time.

Example… When a car is driven, only about 20% of the high-quality energy available in its gasoline fuel is converted into mechanical energy (to propel the vehicle) and electrical energy (to run its electrical systems). The remaining 80% is degraded to low-quality heat that is released into the environment and eventually lost into space.

Example… When electrical energy flows through filament wires in an incandescent light bulb, it is changed into about 5% useful light and 95% low-quality heat that flows into the environment. In other words, this so called light bulb is really a heat bulb.

Energy Efficiency A measure of how much useful work is accomplished by a particular input of energy into a system. ENERGY CAN NEVER BE RECYCLED OR REUSED. IT IS ALWAYS TRANSFORMED FROM HIGH QUALITY TO LOW QUALITY ENERGY

What Does This Have to Do With Food Chains and Food Webs? Food Chain One way flow of energy Food Web Energy flows between many food chains

Vocabulary to know.. Photosynthesis - Cellular respiration Chemosynthesis - Hydrothermal vents

What Does This Have to Do With Food Chains and Food Webs? A large percentage of the energy is lost between trophic levels. This is as a result of the following: Some of the organism cannot be eaten, e.g. bones, fur, etc. Once eaten, some of the organism cannot be digested. Energy is lost in excretory materials, such as urine. Energy is lost in the form of heat from respiration and body heat.

Let’s Practice… Give an example of entropy. Energy quality is a measure of an energy sources’ ability to do useful work. What is the difference in high quality energy and low quality energy? Give an example. What are three interconnected factors that life on Earth depends?

Let’s Practice State the 1 st and 2 nd Laws of Energy (thermodynamics). Someone wants you to invest money in an automobile engine that will produce more energy than the energy in the fuel (such as gasoline or electricity) you use to run the motor. What is your response? Explain.

Let’s Practice… Use the 2 nd energy law to explain why a barrel of oil can be used as a fuel only once? Why do you continuously need to eat food?