Explain how the plant described below would respond to light and how it could survive as a result of its response.

Responses to light are critical for a plant's survival. Consider a sprouting plant left in a closet with only a horizontal sliver of sunlight coming in from the crack at the bottom of the door. 

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Plants exhibit behaviors known as tropisms, which is a response to a stimuli in the environment. Phototropism is the response to light. Due to plant hormones known as auxins, they can bend toward the light. Cells farthest from the source of light have more auxins that react to the light by causing these cells to become elongated than those closest to the light.  This causes the bending effect we see in plants toward a window or light source. This is called positive phototropism and is seen in plant shoots. The seedling would bend towards the light and if it could obtain light energy, it would be able to carry out photosynthesis, and possibly survive. There are many other tropisms--here are two additional examples--geotropism-response to gravity, hydrotropism-response to water.

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How does a plant respond to light, including through what hormone, and how it does survive as a result of its response? Responses to light are critical for plant survical.  Consider a sprouting plant left in the closet with only a horizontal sliver of sunlight coming in from the crack at the bottom of the door. 

Plants have multiple hormones which  asist the plant in its daily functions. One hormone which promotes growth is called Cytokinins. This hormone stimulates cell division and stem formation which will make the plant grow taller. Another regulator hormone called Abscisic Acid. This regulator works with the chloroplast to moderate light intake. 

Through a combination of both of these plants, the plant can and will actually grow towards the light. The Abscisc Acid will first detect the crack of light and send signals to grow with Cytokinins. Through photosynthesis, the plant will have no choice but to bend and attempt to have its fullest part growing in the light so it will actually bend and grow towards the light!

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