Orthotropic movement refers to the directional movement of plants caused by external stimuli in a single direction. It mainly includes phototropic movement, gravitational movement, tactile movement and chemotropic movement. It is an irreversible movement process. According to the above definitions, Which of the following are tropic movements:. ['a puppy that is repeatedly seduced by bones, keeps drooling when it sees the bones again.', 'the root of rice always grows in the direction of more fertilizer in the soil.', 'the morning glory petals unfold in the morning, and the petals close when the sun shines at noon.', 'the shade plant grows better in the shade than in the direct sunlight.']