Green plants are the main . They produce food by using the Sun’s energy to combine water with gas from the air. This process is .

A chain is a convenient way to show how moves among living things in an Here is an example of a food chain.
Using these terms: frog, owl, snake, flower, caterpillar, complete the food chain.
The living things are called the biotic factors, or parts, of the ecosystem; the non-living
things are called the abiotic factors. In the grid below, check off which term matches the right heading: either Biotic or Abiotic factors.
Biotic | Abiotic | |
|---|---|---|
Sun | ||
Air | ||
Grass | ||
Tree | ||
Rotten log | ||
Deer | ||
Water | ||
Gravel | ||
Grasshopper | ||
Bacteria |