If a Researcher Exposes Half of the Subjects in an Experiment

question 4

Multiple Choice

If a researcher exposes half of the subjects in an experiment to condition A and then B, and the other half of the subjects to condition B first and then A, what procedure has been used?

• A) counterbalancing
• B) order effects
• C) switchback
• D) reversal

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Definitions:

Alveolates

A group of protists, including dinoflagellates, apicomplexans, and ciliates, characterized by the presence of alveoli (small sac-like structures) beneath their cell membranes.

Representative Clade

A group of organisms that includes an ancestor and all of its descendants, representing a single branch on the tree of life.

Supergroup

In biology, a high-level classification rank above kingdom, used in some recent taxonomic systems to organize the diversity of life.

Trypanosomes

Single-celled parasitic organisms responsible for diseases like African sleeping sickness and Chagas' disease, transmitted by insect vectors.