Food Webs and Pyramids Biology

Some definitions… Autotroph Heterotroph Herbivore Carnivore Omnivore Decomposer

Food chains

Food Webs

The Flow of Energy Producers - Plants capture the sun’s energy and store it in food Primary Consumers (herbivores) - Animals that receive their energy directly from plants Secondary Consumers (carnivores) - Consumers that feed on primary consumers Energy flow: Sun  producers  primary consumer  secondary consumer  third level consumer  etc…

Ecological Pyramids Biomass - the amount of living biological material in an ecosystem

Energy Pyramid Only 10% of energy is available to next level

10% Rule of Energy Transfer 33% 50% and waste 17%

Biomass Pyramid

Pyramid of Numbers

Better to eat corn or meat??

Let’s Practice Determine the amount of useable energy for the different trophic levels.

Biological Magnification http://www.youtube.com/watch?v=E5P-UoKLxlA

Biological Magnification

OBJ 7 Invasive Species http://www.youtube.com/watch?v=s_onANXeIPA

OBJ 7 Invasive species http://www.youtube.com/watch?v=71RBtamT6vk&feature=related

Frontier of rabbit spread 1860 Figure 37.13A 600 km 1980 1910 1910 1900 1910 1920 1920 1910 1890 1900 Figure 37.13A The spread of rabbits in Australia 1910 1880 1920 1920 1890 1870 1880 Key 1870 Frontier of rabbit spread 1860 19

Figure 37.13B Figure 37.13B A familiar sight in early 20th-century Australia 20

Figure 37.13C Figure 37.13C A cane toad (Bufo marinus) 21