Ricardo scooped up some pond water that contained many green organisms. His teacher suggest that he key out the organisms. what important features should ricardo use to determine if the organisms are plants

The key feature is cell wall. Only plants contain cells with cell wall. The plant cell wall is composed of cellulose. Cellulose is a structural carbohydrate and is considered a complex sugar because it is used in both protection and structure. The plant cell wall consists of three layers with each layer containing its own unique structure and function.