Plants Often Use Changes in Day Length (Photoperiod)to Trigger Events

question 25

Multiple Choice

Plants often use changes in day length (photoperiod) to trigger events such as dormancy and flowering. It is logical that plants have evolved this mechanism because photoperiod changes

• A) are more predictable than air temperature changes.
• B) alter the amount of energy available to the plant.
• C) are modified by soil temperature changes.
• D) can reset the biological clock.
• E) are correlated with moisture availability.

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Definitions:

Bioaccumulation

The concentration of a chemical pollutant in the tissues of an organism rises over the course of the organism’s lifetime.

Greenhouse Effect

Warming of Earth’s lower atmosphere and surface as a result of heat trapped by greenhouse gases.

Primary Production

The production of organic compounds from atmospheric or aquatic carbon dioxide, principally through the process of photosynthesis or chemosynthesis.