Why Is a Longitudinal Design Considered a Within-Subjects Design

question 38

Multiple Choice

Why is a longitudinal design considered a within-subjects design?

• A) Participants are measured twice, once at the beginning of the study and once at the end of the study.
• B) Participants are repeatedly measured on the dependent variable over time.
• C) Participants are measured on the dependent variable after exposure to each level of the independent variable.
• D) Fewer research participants are needed for adequate statistical power.

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Definitions:

Minerals

Inorganic nutrients ingested as salts dissolved in food and water.

Free-Living Flatworms

Flatworms that are not parasitic and live independently in various aquatic or moist terrestrial environments.

Pharynx

The membrane-lined cavity behind the nose and mouth, connecting them to the esophagus.

Digestive Enzymes

Proteins that accelerate the breakdown of food molecules into absorbable nutrients within the digestive system.