Under the standard school-level classification of conventional plastic waste,…

Concept

Biodegradation is the breakdown of a material by living organisms through enzymes that can act on the chemical structure of that material.

In the standard school-level classification, conventional plastics are non-biodegradable because their stable synthetic polymer chains are not broken down by ordinary biological decomposers.

Application

1. Bacteria commonly decompose many natural organic substances, but ordinary environmental bacterial action is not counted as decomposing conventional plastic in this classification.

2. Saprophytes feed on dead and decaying organic matter, but their usual extracellular enzymes do not act on conventional plastic as a biodegradable substrate.

3. Parasites obtain nutrients from a living host; they do not function as decomposers of plastic waste.

Cross-check and contrast

• Bacteria: some specialised strains can act on particular polymers under selected conditions, but that exception is outside the standard classification used in this item.

• Saprophyte: its decomposer role concerns dead and decaying organic matter, not conventional plastic.

• Parasite: its nutrition is host-dependent rather than plastic-decomposing.

• None of the above: this would require every named group to decompose conventional plastic, which conflicts with the stated classification.

Therefore, the accepted response is More than one of the above.