Many Plants Flower in Response to Day-Length Cues

question 70

Multiple Choice

Many plants flower in response to day-length cues. Which of the following statements best summarizes this phenomenon?

• A) As a rule, short-day plants flower in the summer.
• B) As a rule, long-day plants flower in the spring or fall.
• C) Long-day plants flower in response to long days, not short nights.
• D) Flowering in day-neutral plants is only influenced by day length if there is an exceptionally warm spring.
• E) Flowering in short-day and long-day plants is controlled by phytochrome.

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Definitions:

Ex Post Facto

A research design that examines the effects of an independent variable on a dependent variable after the event has occurred.

Random Assignment

A method in experimental design where study participants are allocated to different groups on a random basis to reduce bias.

Experimental

Relating to a controlled study involving variables manipulated to determine cause-and-effect relationships.

Longitudinal

Describes research or analysis that takes place over a long period of time, observing the same subjects to detect changes or developments.