Factors that Affect Photosynthetic Outputs (photosynthetic rate)
Factors Affecting Photosynthesis
Among the most important factors that affect photosynthesis are temperature, light intensity, and availability of water.
Among the most important factors that affect photosynthesis are temperature, light intensity, and availability of water.
Temperature
The best temperatures for photosynthesis to occur are between 0 degrees Celsius (32 degrees Fahrenheit) and 35 degrees Celsius (95 degrees Fahrenheit). Temperatures that are not within the range affect the enzymes that are vital to the process of photosynthesis. At very low temperatures, photosynthesis may stop entirely.
The best temperatures for photosynthesis to occur are between 0 degrees Celsius (32 degrees Fahrenheit) and 35 degrees Celsius (95 degrees Fahrenheit). Temperatures that are not within the range affect the enzymes that are vital to the process of photosynthesis. At very low temperatures, photosynthesis may stop entirely.
Light Intensity
An increased amount of sunlight, or light intensity, is helpful for many plants because this sunlight increases the rate of photosynthesis. But in excess, this can be harmful to plants, which is why after a certain level, the plant reaches its maximum rate of photosynthesis.
An increased amount of sunlight, or light intensity, is helpful for many plants because this sunlight increases the rate of photosynthesis. But in excess, this can be harmful to plants, which is why after a certain level, the plant reaches its maximum rate of photosynthesis.
Availablility of Water
As you have learned, water is fundamental to the process of photosynthesis. Without it, the process cannot happen. A shortage of water can slow and potentially stop photosynthesis. Water loss can also damage plant tissues.
As you have learned, water is fundamental to the process of photosynthesis. Without it, the process cannot happen. A shortage of water can slow and potentially stop photosynthesis. Water loss can also damage plant tissues.
Photosynthesis Under Extreme Conditions
Plants that live in dry climates, where water is a scarce resource, such as a desert, need to conserve water. Plants do this by closing the small 'pore like' openings in their leaves that normally admit carbon dioxide. This helps plants not to dry out, but since the entrances for carbon dioxide are blocked off, carbon dioxide levels plummet. This is why photosynthesis has to stop or slow down.
Other plants, known as C4 plants have a special chemical pathway that allows them to capture even very low levels of carbon dioxide and pass it on to the next step in the process of photosynthesis, the Calvin Cycle. Extra energy is required for this process to take place, but photosynthesis does not have to stop or slow down this way.
Examples: Corn, sugar cane, and sorghum
The other, and final, group of plants are CAM plants. These plants admit air into their leaves only at night. In the cool temperature of the night, carbon dioxide can combine with molecules to form organic acids. During the day, the leaves are tightly sealed to prevent the loss of water. This process enables carbohydrate production.
Examples: Pineapple trees and cacti
Plants that live in dry climates, where water is a scarce resource, such as a desert, need to conserve water. Plants do this by closing the small 'pore like' openings in their leaves that normally admit carbon dioxide. This helps plants not to dry out, but since the entrances for carbon dioxide are blocked off, carbon dioxide levels plummet. This is why photosynthesis has to stop or slow down.
Other plants, known as C4 plants have a special chemical pathway that allows them to capture even very low levels of carbon dioxide and pass it on to the next step in the process of photosynthesis, the Calvin Cycle. Extra energy is required for this process to take place, but photosynthesis does not have to stop or slow down this way.
Examples: Corn, sugar cane, and sorghum
The other, and final, group of plants are CAM plants. These plants admit air into their leaves only at night. In the cool temperature of the night, carbon dioxide can combine with molecules to form organic acids. During the day, the leaves are tightly sealed to prevent the loss of water. This process enables carbohydrate production.
Examples: Pineapple trees and cacti
(Miller & Levine Biology, 2011)
(Krueger, 2012)
(Krueger, 2012)