Fact 1: Energy is passed up a food chain or web from lower to higher trophic levels.

Fact 2: Food gives energy.

Given the two facts above, answer the question "What is passed up a chain or web from lower to higher trophic level?" with the following options: 
- Veins and arteries.
 - heat or cold
 - scarce resources
 - food resources
 - matter vibrating
 - rays or beams
 - Organic compounds
 - fossil fuels


 

    food resources     