Charles and Francis Darwin Concluded from Their Experiments on Phototropism

question 65

Multiple Choice

Charles and Francis Darwin concluded from their experiments on phototropism by grass seedlings that the part of the seedling that detects the direction of light is the

• A) tip of the coleoptile.
• B) part of the coleoptile that bends during the response.
• C) base of the coleoptile.
• D) cotyledon.
• E) phytochrome in the leaves.

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Definitions:

True Experimental Design

A research design that includes random assignment of participants to conditions and manipulation of an independent variable to determine its effect.

Random Assignment

A method used in experiments for distributing participants among various groups in a study, ensuring that each has an equal chance of being assigned to any group, to minimize bias.

Field Settings

Real-world environments outside of the laboratory where research is conducted or observations are made in a natural context.

Quasi-Experimental Design

A research design that attempts to establish a cause-and-effect relationship but does not employ random assignment to conditions, making it less strict than a true experimental design.