Pain is usually connected to a nervous system. When you put your hand too close to a hot stove, nerve cells send a warning of danger to your brain.That, in turn, causes you to pull your hand away before any serious damage is done. Plants don't have nerves or brains, so they can't feel pain like you do.And since they can't escape a potentially dangerous situation, they need other ways of fighting back.
The biggest threat to a plant's life is getting eaten. Some plants discourage plant- eaters from chewing on them by growing thorns or sharp little hairs, like a rose or a cactus does. Other plants produce bad-tasting or even toxic chemicals.
But a plant called bittersweet nightshade does something even more smartly. When a slug, a small creature, chews holes in a nightshade's leaf, a kind of sweet juice begins dripping out of the edges of the wound, almost as if the plant were bleeding.In their quest to collect the juice, the ants gather all over the injured nightshade plant and attack anything that stands in their way —— including the slug that damaged the plant in the first place. In short: Slug attacks plant; plant calls army of ants to come closer to kill slug. Thus, the plant can help itself by calling the enemies of its own enemies.
But they have armies of cold-blooded killers always ready to obey their orders.
A. Plants may look like passive victims.
B. Your brain recognizes that signal as pain.
C. This sweet juice successfully drives the slug away.
D. Your brain is definitely a complex nervous system.
E. The sweet juice happens to be a favorite food of ants.
F. These force potential attackers to abandon their meals.
G. But plants definitely do recognize when something is hurting them.
