So back to those sunflowers. They sense the light from the sun and turn to face it. We know they sense the sun because they respond to it by changing position.
Some plants close up their leaves or flowers every night and open them again in the morning. Other plants close their leaves when touched..
Scientists have done an experiment where they played the sound of an insect munching on leaves to plants, and the plants released defensive chemicals, even though there wasn't actually an insect there.
Scientists think that plants have many senses that are similar to ours. Of course, they don't have ears or noses, but scientist have shown that plants can sense sound, gravity, the presence of water, or detect a rock or other object in the soil and bend their roots to avoid it.
One reason we don't usually notice what plants are doing is because they are so slow. If we watch a time-lapse video, then we can start to see their behavior.
What do you think now?