Food Web Notes

Food Chain:

Sun --> Wheat (Producer (Autotroph)) --> Mouse (Consumer (Heterotroph)) --> Cat (Consumer (Heterotrophs)) --> Wolf (Consumer (Heterotroph).

The word troph means feed. Wheat is at the first trophic level, mouse is at the second trophic level, etc. Mouse is a primary consumer, cat is a secondary consumer, wolf is a tertiary consumer. 

If I have 1 Kg of wheat with an energy value of 1000 kJ. Wheat (1000 kJ) --> Mouse (100 kJ) --> Cat (10 kJ) --> Wolf (1 kJ). In a food chain the amount of energy available for the consumer in the trophic level above is 10%. The remaining 90% is used to live and grow. Heat is also emitted from your body.

Food Web:

A food web is composed of all of the feeding relationships in a community. 

Herbivore --> Eats Producers ONLY (photosynthetic).

Carnivore --> Eats Consumers ONLY.

Omnivore --> Eats Producers and Consumers.

Pyramids of Energy (Numbers):

Level 4: Little: Hawk: 4th Trophic Level: 1

Level 3: A Bit: Snakes: 3rd Trophic Level: 365

Level 2: Some: Mice And Squirrels: 2nd Trophic Level: 266 450

Base: Lots: Plants And Grasses: 1st Trophic Level: 97 254 250