Do some plants also move?
Does plants also walk
One of the fundamental differences between plants and animals is that animals can move from place to place whereas plants lack mobility. But there are some plants which move on their own. Some types of algae have whiplike flagellas they use to paddle themselves through water. Many plants particularly the lower ones produce mobile male gametes which swim about in order to find eggs to fertilize. Englena is a protozoa which is capable of swimming.
Apart from these exceptions the movement of plants is usually confined to the movement of some parts of it while the plant itself remains fixed at one place. There are three basic types of plant movements: tropisms, nutations and nastic movements.
1) A tropism is a growth response towards or away from something caused by a specific environmental stimulus. The direction of growth is determined by stimulus it is called positive tropism and when away from it, it is called negative tropism. Tropisms are caused by spacial growth hormones called auxins. In most of the cases the stimulus causes the auxins to collect on one side of an affected organ. This causes the cells on that side to grow and divide more quickly than the cells on the other side. As a result the organ bends away from the side with the most auxins.
2) Nutation is the spiral movement exhibited by the tips of certain stems during growth which enables a clibing plant to find a suitable support.
3) Nastic movement is caused by an external stimulus such as light or temperature but the movement is independent of the source. For example some flowers open in daylight and close again at night. Flowers like daisy open only when the temperature is just right.