Energy enters ecosystems in the form of 
wind warmth light glucose photons sun's heat heat expelled
A B C D E F G H
Sunlight is composed of photons, or particles of solar energy.
Energy enters ecosystems in the form of photons
Energy enters ecosystems in the form of  (A) wind (B) warmth (C) light (D) glucose (E) photons (F) sun's heat (G) heat (H) expelled