There are five common stimuli in the environment : light, gravity, chemicals, water and touch (or contact). These five stimuli give us five types of tropisms : phototropism, geotropism, chemotropism, hydrotropism and thigmotropism. In phototropism, the stimulus is light ; in geotropism the stimulus is gravity, in chemotropism the stimulus is a chemical, in hydrotropism the stimulus is water, and in thigmotropism the stimulus is touch (of a solid surface). It is obvious that the tropisms are named according to the stimulus.1. The movement of a plant part in response to light is called ________.(i) Phototropism(ii) Geotropism(iii) Chemotropism(iv) Hydrotropism2. The movement of a plant part in response to gravity is called _________.(i) Phototropism(ii) Geotropism(iii) Chemotropism(iv) Hydrotropism3. The movement of a plant part in response to a chemical stimulus is called _________.(i) Phototropism(ii) Geotropism(iii) Chemotropism(iv) Hydrotropism4. The movement of a plant part in response to water is called __________.(i) Phototropism(ii) Geotropism(iii) Chemotropism(iv) Hydrotropism5. The directional growth movement of a plant part in response to the touch of an object is called _______.(i) Phototropism(ii) Geotropism(iii) Chemotropism(iv) Hydrotropism