The Effect of Darkness on Photosynthesis

The Effect of Darkness on Photosynthesis
••• Image by, courtesy of Sean McGrath

Plants and some single-celled organisms use photosynthesis to transform water and carbon dioxide into glucose. Light is essential to this energy-generating process. When darkness falls, photosynthesis stops.


During daylight hours, plants perform photosynthesis, storing energy that will help them reproduce and grow.


Photosynthesis stops when the sun sets. During night hours, most plants switch from photosynthesis to the opposite process, respiration, in which carbon dioxide and water are produced rather than consumed.


According to the National Park Service, cacti and other succulents open their stomata to take in carbon dioxide at night rather than during the day, thus avoiding unnecessary moisture loss. That carbon dioxide is then held until daylight returns and photosynthesis resumes.


Some plants experience a longer dormancy period in wintertime. For instance, Rocky Mountain evergreens at high elevations perform photosynthesis on only the winter's sunniest and warmest days.

Food Chain

The same stored energy that plants use to grow and reproduce later nourishes humans and other animals who ingest the plants. Even carnivorous animals benefit indirectly from photosynthesis when they eat animals that have eaten plants.

Related Articles

How Does Summer Affect the Lives of Plants & Animals?
The Three Stages of Photosynthesis
Why Do Plants Need the Sun?
Organelles Involved in Photosynthesis
What Is the Sun's Role in Photosynthesis?
Definition of Plant Respiration
Why Is Photosynthesis So Important to Plants?
How Do Plant Cells Obtain Energy?
The Effect of Temperature on Pea Respiration
What Is the Advantage of C4 Photosynthesis?
Phases of Photosynthesis & Its Location
How Does Darkness Affect Plant Growth?
What Is Reduced & Oxidized in Photosynthesis?
The Greenhouse Effect & Photosynthesis
Ideal Conditions for Photosynthesis
Where Is Starch Stored in Plant Cells?
What Kind of Flowers Are in the Tundra Biome?
What Are the Functions of Photosynthesis?
What Is the Waste Product of Photosynthesis?
How Do Plants Store Energy During Photosynthesis?