You are concerned with surveying the protozoa in the arboretum soil. While most commonly thought to live exclusively in aquatic environments, protozoa can play an important role in the nutrient cycling that takes place in soil. In addition, protozoa can help maintain the proper balance of bacterial populations within soil, as bacteria are a primary source of food for protozoa. Protozoa are extremely diverse. However, there are three characteristics common to all organisms called protozoa. What are these three characteristics

eukaryotic, unicellular, without a cell wall

Explanation:

Protozoans are single-celled eukaryotes that generally move through cilia, flagella, or amoeboid motion. After their discovery, protozoans were considered as single-cell animals due to their animal behavior (including predation and motility), and because they don't have a cell wall, as observed in algae and plants. Some examples of protozoans include Paramecium, Amoeba, and Trypanosoma. Nowadays, the term 'protozoans' is still used to describe unicellular eukaryotic organisms from the Protista kingdom that are heterotrophs, i.e., unicellular microorganisms that acquire energy and nutrients from other organic sources, especially plant and animal matter.

that scientist would be robert hooke

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.