C4 plants

C4 plants are a type of plant that use the C4 photosynthetic pathway. This pathway is an adaptation to high light intensities, high temperatures, and dryness. C4 plants include several thousand species in at least 19 families of plants.

Overview

The C4 pathway was first discovered by Melvin Calvin and his colleagues during the 1960s. The name "C4" comes from the four-carbon compound that is the first product of the C4 photosynthetic pathway. This pathway is an alternative to the more common C3 pathway.

C4 Pathway

In C4 plants, the process of photosynthesis is divided between mesophyll and bundle sheath cells, two types of cells in the leaves. This division of labor allows these plants to avoid the process of photorespiration, a wasteful reaction that occurs when the enzyme RuBisCO captures oxygen molecules instead of carbon dioxide.

Adaptations

C4 plants have several adaptations that allow them to survive in hot, dry environments. These include:

• Increased water use efficiency
• Higher rates of photosynthesis when light is intense and temperatures are high
• The ability to suppress photorespiration

Examples of C4 Plants

Examples of C4 plants include maize, sugarcane, sorghum, and many species of grass and weed. These plants are often found in tropical and subtropical regions, as well as in grasslands and deserts.

See Also

• C3 Plants
• CAM Plants
• Photosynthesis
• Photorespiration