1. Energy Flow and Food Webs
Ms. Petrauskas

2. The spheres
Hydrosphere: all of the earths water (as a solid, liquid or gas)
Lithosphere: the earths solid outer layer (rocks, earth etc.)
Atmosphere: the layer of gases surrounding the earth
Biosphere: the zone around the earth where life can exist ( part of the lithosphere, hydrosphere and atmosphere)

3. Source of all energy… Radiant energy- the energy radiated from the sun
Composed of ultraviolet rays and visible light
70% absorbed by the hydrosphere and the lithosphere and converted to thermal energy
Thermal energy warms the earth
The rest goes back to space

4. Solar Radiation Distribution

5. Photosynthesis
Light energy is used by some organisms and is converted to chemical energy (plants, some algae and some protists)
Carbon dioxide + water sugar + oxygen
Carbon, Oxygen, and Hydrogen are rearranged via light energy into sugar and oxygen
Light Energy

7. Cellular Respiration
The process by which sugar and oxygen are converted to carbon dioxide and water to provide energy for the cell (Ex. Human cells use sugar to make energy)
Sugar +Oxygen carbon dioxide +water

8. Equilibrium
A balance of photosynthesis and cellular respiration are part of a stable and healthy ecosystem

9. Trophic levels Autotroph –producer Primary consumer – herbivore
Secondary consumer – usually carnivore or omnivore
Tertiary consumer- usually carnivore/ omnivore/ detrivore
Decomposer

10. A. Autotrophs (Producers)
Organisms that photosynthesize ( produce their own food)
Ex. Plants, algae and some bacteria

11. B. Heterotrophs (Consumers)
Organisms that must consume (eat) other organisms to obtain energy and building materials
4 types of consumers depending on what they eat. (Herbivores, Carnivores, Omnivores, Scavenger/ Detrivores)

12. 1. Herbivore Eat only plants
Ex. Deer, giraffes, cows, pandas, humming birds, grasshoppers

13. 2.Carnivores Eat only animals (including insects)
Ex. Killer whales, praying mantis, lions, tigers, wolves, hawks

14. 3.Omnivore Eat both plants and animals
Ex. Bears, robins, raccoons, blue jays, fox, humans

15. 4. Scavengers/Detrivores
Feed on dead or decaying animal matter
Ex. Crows, crayfish, vultures –Scavengers
Ex. Worms, wood beetles

16. C. Decomposers Another trophic level
Consume remaining dead or decaying material
Break down organic matter to its nutrients
Nutrients are returned to the soil
Ex. Mould, yeast, mushrooms

17. Food chain
A series of predator-prey relationships (predators eat prey)
Each chain begins with the sun
Producers are next as they use the sun’s energy to produce glucose
Consumers eat the producers
Decomposers return nutrients to the soil

20. Create your Own food chain
Start with the sun producer  primary consumer secondary consumer tertiary consumer  end with the quanternary consumer or decomper
Arrows point in the direction of energy flow.
TRY IT!!!!!!

21. Food Webs
A more accurate way to show feeding relationships within a community
Consumers feed on many species, therefore reducing the vulnerability of any one prey species and reliability on one prey species
Useful to see what happens when one species is removed from the web or added to the web (invasive species)

24. Ecological Pyramids
Display relationships between trophic levels. As the pyramid narrows it shows that energy has been lost
Can represent energy, biomass or numbers of organisms

25. Energy loss As one organism consumes another energy is transferred
Some energy is lost as thermal energy
Consider how much heat you lose compared to a plant!
Only 10% of the energy consumed by one trophic level is passed onto the next trophic level

26. 10% is transferred between trophic levels
Carnivore (20J)
Herbivore (200J)
Plants(2000J of sun’s energy)

27. Create your own…..start with 1,000,000J of energy
100,oooJ
10,000J
1,000J
100 J

28. Analogy Cut a pie into 10 equal slices
Only 1 piece is available to the next trophic level
Cut that slice into 10 smaller slices
Only 1 of those is available to the next trophic level

29. Biomass Pyramid: mass of all living organisms in an area
Predator, parasites
Insect herbivore
Grass

30. Normal