An Experimenter Tests the Hypothesis That Physical Exercise Improves Mood

question 19

Multiple Choice

An experimenter tests the hypothesis that physical exercise improves mood. Subjects in the experimental group participate on Monday and Tuesday and those in the control group on Wednesday and Thursday. Which of the following is the extraneous variable?

• A)Hypothesis
• B)Day of the week
• C)Exercise
• D)Mood (degree of happiness)

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Definitions:

Uterus

The hollow organ within females in which the embryo and fetus develop.

Embryo

An early stage of development in multicellular organisms, in humans, it refers to the period from conception to the eighth week of pregnancy.

Fetus

A developing human from roughly eight weeks after conception until the time of birth, characterized by rapid growth and development of organs and structures.

Mutations

Changes in the DNA sequence of an organism's genome, which can lead to variations in physical traits or the development of diseases.