What are the adaptations of a Barrel Cactus?
Both cacti share the same main adaptations: A swollen trunk which stores water, a shallow root system to catch water whenever it rains, rounded shape and no leaves to minimise water loss. They also have a special metabolism which allows the stomata to stay closed during daytime when water loss would be greatest, opening at night to release oxygen and absorb carbon dioxide which is stored as malate which is then used in photosynthesis during the day.
