1. The study of the environment in relation to organisms/people
ECOLOGY
The study of the environment in relation to organisms/people

2. ECOSYSTEM
A community of animals, plants, & microscopic life that interact in a particular place in the environment.
Penguins live with polar bears, ducks, foxes, seals, & wolves in a cold environment.

3. FOOD CHAIN
A pathway of food & energy through an ecosystem. Each species in the chain depends on the other in some way.

4. Each has a role (producer/consumer)
Producer-one who makes food
Consumer-one who eats food

5. Acorns--- mouse--- owl Grass--- sheep--- people
FOOD CHAIN EXAMPLES
Acorns--- mouse--- owl
Grass--- sheep--- people

6. Chapter 11
Energy Resources

7. 90% of all energy comes from fossil fuels
Formed millions of years ago from the remains of dead plants & animals.
The remains decay & get buried in mud, & clay. Over millions of years, heat & pressure change the sediment into fossil fuels.

8. Fossil Fuels
3 main fossil fuels are: coal, oil, natural gas
Fossil fuels are useful as an energy source because they are rich in hydrocarbons.

9. Substances that contain the elements hydrogen & carbon.
HYDROCARBONS
Substances that contain the elements hydrogen & carbon.

10. COMBUSTION
Process in which hydrocarbons in fossil fuels are combined with oxygen at high temps to release heat and light energy.
Also called BURNING.

11. ADVANTAGES OF F.FUELS
Produce more heat than wood does
Are easier to transport, store, and use than wood.

12. When coal is burned, it releases pollutants (sulfur) into the air.
DISADVANTAGES
When coal is burned, it releases pollutants (sulfur) into the air.
Nonrenewable

13. 1-2 Solar Energy Energy from the sun
Solar energy received by earth in one day could meet the world’s energy needs for 30 years.
Most of the solar energy that hits earth is unused.

14. USES OF SOLAR ENERGY
Heat homes (and water)
Produce electricity

15. To be useful, the sun’s energy must be collected, stored, & converted.

16. At night, pull down shades to keep the heat in.
PASSIVE SOLAR HEATING
Windows of a building are positioned so that sunlight enters directly & heats the building.
At night, pull down shades to keep the heat in.

17. PROBLEMS
1. Need for a backup system
(At night?, rain?,)
2. It only heats part of the house.

18. ACTIVE SOLAR HEATING
Involves collecting the sun’s energy in a device called a solar collector.
Solar collector – a black surface covered with glass which absorbs energy from the sun & converts it to heat.

19. How it works?
Pipes are filled with water in the solar collector. The water gets heated & is pumped down to a storage tank. Then the heated water is pumped throughout the house giving off heat where needed. Water cools & returns to the solar collector to be reheated by sun.

20. Active Heating Diagram

21. PROBLEMS Depends on time of day,& weather conditions
Solar devises expensive

22. SOLAR CELLS
Photovolatic cell- a solar cell that converts light energy into electricity.
Solar calculator, solar phone.
Produces a small amount of electricity & are costly.

23. POWER TOWER
An array of mirrors that focus sunlight onto a boiler mounted on a tower. The sunlight heats the water in the boiler & converts it to steam. The steam turns a turbine to generate electricity.

24. 1-3 Wind & Water Energy
Past Uses of wind: propel ships, pump water from wells
Past Uses of water: grind corn
Today both are used to produce electricity

25. Wind Winds are caused by the uneven heating of the earth by the sun.
An indirect form of solar energy.

26. Advantages of Wind Energy
Saves fossil fuels
Runs clean, reduces pollution
Natural resource
Light weight & easy to install

27. Disadvantages Doesn’t work on calm days
Windmills are easily knocked down/broken
Limited to geographical areas like Great Plains, Mountains, and Coast.

28. Water Energy
Another indirect form of solar energy. The sun powers the water cycle.
Sun evaporates water from lakes, and oceans, Water vapor condenses to form clouds, & vapor changes to rain and falls from sky.

29. Hydroelectric Power
The use of mechanical energy of falling or running water to generate electricity.
Example: Hoover Dam

30. How it works
A dam is built to hold back tons of water in a reservoir. Water is drawn into the power plant through pipes. Water is pushed through the pipes & turns the blades of several turbines which turn the electromagnets on the generators to produce electricity.

31. Advantages
Clean, no pollution, natural
Efficient means to make electricity
Fairly cheap

32. Disadvantages Limited areas to construct big dams
Harmful to environment-could alternate patterns of fish migration, can cause flooding.

33. 1-4 Nuclear Energy
Energy locked within the atomic nucleus
Atom- basic building block of matter. All objects in the world are made of matter & thus of atoms.

34. Nucleus Makeup
1. Protons- positively charged particles found in nucleus
2. Neutrons- neutral or no charge, found in nucleus
3. Electrons- whirls around nucleus, negatively charged

35. Nucleus Diagram

36. Einstein's Prediction
If a nucleus of an atom could be split, a new & powerful energy source would be produced.

37. Nuclear Fission
The splitting of an atomic nucleus into 2 smaller nuclei during which nuclear energy is released.

39. Most Common Type of Fission Reaction
Splitting of Uranium-235 nucleus

40. Fission Reaction Steps
1)Scientists shoot a “nuclear bullet”(neutron) into the nucleus.
2)neutron strikes Uranium-235 nucleus & splits into 2 smaller nuclei.
3)2 or more neutrons are released along with energy

41. Each Neutron released during a fission reaction by splitting another Uranium-235.

42. Nuclear Chain Reaction
Process in which the splitting of one nucleus causes the splitting of additional nuclei.

43. Controlled N. Chain Reaction
If controlled, the energy can be a valuable energy source. Nuclear Power Plant.
If uncontrolled, it creates a huge explosion like the atom bomb.

44. Produce electricity from energy locked within the nuclei of atoms.
Nuclear Power Plants
Produce electricity from energy locked within the nuclei of atoms.

45. Uranium 235 is mined & put on fuel rods in the reactor vessel.
How it works
Uranium 235 is mined & put on fuel rods in the reactor vessel.
2. Water is pumped in & neutrons strike the fuel rods (fission begins).

46. 3. Heat energy converts water into steam.
4. Steam passes through pipes & spins the blades of a turbine which turns the magnets in the generator to produce electricity.

47. 5. Water cools & is recycled back to reactor vessel
5. Water cools & is recycled back to reactor vessel. Some is dumped into stream.

48. To Control Nuclear Fission
Drop in the control rods.
Control rods act like magnets & absorb all the neutrons which slows down fission reactions.
To speed up fission, take out control rods.

49. Problems 1) Safety- A) radiation leaking into environment
B) what to do with radioactive wastes
C) melt down overheating
D) security-terrorists.

50. 2) money- expensive to build

51. Nuclear Fusion
Combining of 2 atomic nuclei to produce 1 larger nucleus & release energy.
2 Hydrogen’s join to form a Helium & energy is released.

52. Advantage’s Produces far more energy than fission.
Produces less waste.
Hydrogen’s can be obtained from water-(water is abundant)

53. Fusion Problem
Needs more research to solve high temps. and high pressure problems, needed for fusion. Can’t happen naturally on earth.

54. Alternative Energy Sources
1-5
Alternative Energy Sources

55. Energy is produced from heat energy with in the Earth.
Geo Thermal Energy
Geo=Earth Thermal=Heat
Energy is produced from heat energy with in the Earth.

56. Hot Spots
Molten rock within the Earth that comes close to Earth’s surface.

57. Geyser
When water comes in contact with hot spots, water is heated & bursts from the Earth into fountains of hot water & steam.

58. How it works Steam from geysers is used to generate electricity.
Wells can be drilled into hot rock, heat turns water into steam. Steam is pumped to surface and used for electricity.

59. Problem
Number of Hotspots on the Earth is limited so it is unlikely to keep pace with the worlds energy needs.