All materials within ecosystems can be recycled.

All the things expect enegry are recycled.

Explanation:

When the decomposer decomposes the organic substances than they are taken by plants in the form of nutrition and minerals. Likewise, the food prepared by the plants are taken by animals and the nutrition is recycled. The oxygen and carbon dioxide cycle is also recycled. When the animals releases carbon then the plants take it and gives out the oxygen. In this way oxygen and carbon dioxide cycle is also maintained in nature.

But incase of enegry it cannot be recycled but frequently transfered from one form to another form.

hope it helps..

Atissue is a group of connected cells that have a similar function within an organism.