Understanding:
• Chemical energy in carbon compounds flows through food chains by means of feeding
Energy enters most ecosystems as sunlight, where it is converted into chemical energy by producers (via photosynthesis)
- This chemical energy is stored in carbon compounds (organic molecules) and is transferred to heterotrophs via feeding
Trophic Levels
The position an organism occupies within a feeding sequence is known as a trophic level
- Producers always occupy the first trophic level in a feeding sequence
- Primary consumers feed on producers and hence occupy the second trophic level
- Further consumers (e.g. secondary, tertiary, etc.) may occupy subsequent trophic levels
The trophic levels in a community are:
Food Chains
A food chain shows the linear feeding relationships between species in a community
- Arrows represent the transfer of energy and matter as one organism is eaten by another (arrows point in direction of energy flow)
- The first organism in a food chain is always a producer, followed by consumers (primary, secondary, tertiary, etc.)
Examples of Food Chains in Different Habitats
Term: Grassland Food Chain Marine Food Chain Pond Food Chain