This soil structure consists of thin, flat plates of soil that lie horizontally. Usually found in compacted soil?

Aggregates

Explanation:

Aggregates are thin flat plates that lie horizontally. Usually present in compacted soils, or clay deposits. This type of structure stimulates slow water infiltration.

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an active site is a region that is present on an enzyme where the reactants or the substrate molecules we can say bind and experience a chemical reaction. the substrate is basically a reactant whose concentration is changing and that is converting into a product after binding at the active site of an enzyme