What are three environmental factors that affect photosynthesis?

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Photosynthesis is a mechanism that is crucial to the survival of plants. Because photosynthesis determines the amount of food a plant can generate, the rate of photosynthesis determines the rate of growth of plants. There are many factors affecting photosynthesis, predominantly environmental conditions.

Any changes in these environmental changes may disrupt or encourage plant growth. Understanding the effects of these environmental factors provides significant help in solving plant distribution problems.


Light's three primary characteristics affect the rate of plant growth. These characteristics include: quantity, quality and duration. The quantity of light determines the plant's capacity to manufacture its own food. In photosynthesis, the more sunlight a plant absorbs, the higher its capacity to sustain itself. Light quantity affects the rate of photosynthesis. If there is limited light then food production also slows down. Light quality also affects plant growth because the light's wavelength of colour also determines the amount of light a plant can absorb. For instance, green light is not as helpful to plants because most plants reflect green and barely absorb it. Blue light, on the other hand, helps leaf growth. Blue light also encourages flowering, and red light spurs leafy growth as well. Light duration is also important because the length of time a plant is exposed to sunlight also determines the amount of sunlight absorbed. The longer a plant is exposed to sunlight, the more sunlight it can get and the more photosynthesis it can do.


Temperature has the capacity to encourage or inhibit plant growth depending on its variety. Specifically, temperature can affect the rate of respiration in plants. This means that if the temperature does not match the plant variety, it can increase the rate of respiration. When this happens, products of photosynthesis are used more rapidly. Wrong temperature raises the rate of respiration above photosynthesis. Plant growth is inhibited because it cannot manufacture sufficient food. For plants to grow well, the rate of photosynthesis should be higher than respiration. Some plants thrive well in warm weather while others prefer colder temperatures.

Carbon Dioxide

Carbon dioxide is an important element in photosynthesis. Basically, carbon dioxide is synthesised together with water and air molecules using the sun's energy to produce both oxygen and glucose. Glucose is further converted into other components such as fats, starch, enzymes, proteins and DNA/RNA. These components are crucial to overall composition of the plant and its survival.