Food Chain Trophic Levels YouTube Lecture Handouts
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Food Chain, Food Web and Ecological Pyramids - 3 Key Concepts in 1 Lecture
Food Chain Food Web Pyramids Bio-Magnification
This lecture explains what are food chains, food webs and ecological pyramids. She further explains the 3 types of ecological pyramids like pyramid of number, pyramid of biomass and pyramid of energy. She explains the possible cases including the upright and inverted pyramids.
Pyramid of Number
- Number of organisms at different trophic levels of food chain.
- Successive links of trophic structure decrease rapidly in number.
- Ignores biomass of organisms and energy transferred.
Pyramid of Biomass
- Indicates decrease of biomass in each tropical level from base to apex.
- Biomass of the producers is more than biomass of the herbivores
Pyramid of Energy
- Energy pyramid indicates role of organisms in the transfer of energy.
- Illustrates energy needed as it flows upwards.
- Total energy small organisms assimilate and pass on, may be considerably greater than that of organisms with a much larger biomass.
- Energy pyramids slope because less energy is transferred from each level than was paid into it
- Bio-concentration
- Bioaccumulation
- Bio-magnification
✍ Manishika