State the names of two types of plant movements.
Answers
"Plants are stationary but they exhibit movements. There are two types of movement are of induced and automatic.
1. Induced movements are caused due to external stimuli. These could be
a) Tropic: The plant moves to the direction of stimulus which could be geotropism (gravity), phototropism(light), thigmotropism (touch), hydrotropism (water), and chemotropism (chemical).
b) Nastic: The plant grows based on its form and structure on getting stimulus, like photo nasty and thermo nasty.
c) Tactic: Here the whole plant or a part of it moves towards the direction of stimulus, as in bacteria and algae. Movement is dependent on light, heat and chemical substances.
2. Automatic movements do not require external stimulus. It is of two types' movements of variation and growth movement. Examples are growing tip of root and stem or the leaves of Desmodium."