Answer:
Sun
Sun is the main source of energy on earth. About 40% light reach to the atmosphere some of which is filtered by ozone layers, water vapours and other gases. only 1% light is used in photosynthesis.
Photosynthesis
Producers contain chloroplast filled with chlorophyll molecules. when sunlight falls on leaves process of photosynthesis occurs which convert light energy into chemical energy in the form of glucose.
Respiration
Respiration occurs both in producers and consumers. in this process chemical energy (glucose) is converted into ATP, NADH and FADH2.
Decomposition
there are some organisms known as decompose s. they decompose dead bodies of plants and animals and convert complex molecules into simple nutrients with help of energy. in this way sun light energy is transferring in ecosystem in different forms.
Diagram