1. ENERGY MOVEMENT THROUGH ECOSYSTEMS Section 1.11 Section 13.2

2. Radiation The transfer of energy by electromagnetic (light) waves (Electromagnetic Spectrum) Does not require a medium to travel through Travels in straight lines Is emitted by all matter The ONLY form of energy given to us by the sun

3. Solar Energy (Radiant Energy) Comes from nuclear fusion reactions in the sun Reaches Earth by travelling from the sun in waves of different energy levels, collectively known as the Electromagnetic Spectrum

4. Electromagnetic Spectrum In order from lowest to highest energy level: Radio Microwave Infrared Visible Light (see diagram) Ultraviolet X – Rays Gamma

6. EMS Video https://www.youtube.com/watch?v=m4t7gTmBK3g

7. Albedo Effect When solar energy strikes an object, some of the energy is absorbed and some is reflected Albedo is a measure of the percentage of light which a material will reflect High Albedo = large percentage of light reflected Low Albedo = small percentage of light reflected Ex: Polar Ice Cap – High or Low? Black Roof – High or Low? Bare Soil – High or Low?

8. Why is Solar Energy Important? All forms of life are dependent on solar energy for life We need it for plants to grow and to keep earth warm enough for us to survive Photosynthesis – The process by which green plants use sunlight to produce sugar 6CO 2 + 8H 2 O + sunlight 6O 2 + C 6 H 12 O 6 + 2H 2 O Carbon dioxide + water + sunlight oxygen + sugar + water

10. Of the 0.023% of sunlight, how does the energy disperse throughout food chains and food webs? Food Web – a series of interlocking food chains When talking about food webs and energy, new terms are used to describe producers and consumers/ decomposers.

11. Autotrophs Plants or algae which make their own food using the sun’s energy through photosynthesis Previously called producers

12. Heterotrophs Animals, fungi and bacteria that must eat or decompose plants or animals (and their waste) to get their energy Previously called consumers (herbivores, carnivores, omnivores) / decomposers

13. Why New Terms? Each of the feeding levels (producer, primary consumer, secondary consumer….) is called a trophic level Every time something is consumed in a food chain, energy is passed along Less and less energy is passed along each time because some of the energy is used for life processes (maintaining body temperature, digestion, growing, movement etc)

15. With these new terms and previous old terms, we can place labels on organisms within food chains and food webs Handout: Energy Loss in a Food Chain (The Energy Pyramid)

17. The higher the trophic level in a food chain, the more energy is lost Consuming plants (which are the lowest trophic level) allows for the least amount of energy to be lost

18. Homework Food Web Assignment Text Pg 39 # 1-6, 9, 10