Articles > Quizzes & Surveys > Lights’ Effect on Growth – Quiz Lights’ Effect on Growth – Quiz Quiz Choose the best answer. 1. Plants are the primary producers in any ecosystem. True, because other organisms depend on them for food. True, because they can manufacture their own food by photosynthesis. False, because they belong to the consumers, not producers. False, because they depend on sun for light energy. 2. Short day-long night plants require longer periods of darkness. True. These plants only flower when the level of sunlight is fewer than 12 hours. True. These plants only flower when the level of sunlight is more than 12 hours. False. They require longer periods of daylight to bear flowers. False. They need more than 12 hours of light. Otherwise, they tend not to bear flowers if that light exposure requirement is not met.. 3. Photoperiodism refers to the length of light that a plant will react to. True. Plants react through the phytochromes that vary in form and therefore enables plants to react depending on the absorbed wavelengths. True. It pertains to the duration of darkness that is stimulated by a pigment called phytochrome. False. It refers to the movement response of a plant to light. False. It is called phototropism. 4. Plants are able to "know" whether it is daytime or night time through the phytochrome. True. That's because phytochromes are organelles that are sensitive to different light wavelengths. True. That's because phytochromes are pigments responsible for light-sensitive processes. False. Photoperiodism is detected not by phytochromes but by their mitochondria, the powerhouse of the cell. False. Plants lack phytochromes and so are able to determine daytime from night time. 5. Photoperiodism accounts for plants to thrive on any place on Earth. True. Photoperiodism explains how plants are able to thrive on all ecosystems. True. Photoperiodism is responsible for the predominance of any type of plants all over the world. False. It is not photoperiodism. False. Photoperiodism explains how not all plants can thrive on all places, especially in extreme latitudes. Send Your Results (Optional) Your Name To Email Time is Up!