One of the main factors that affect the growth of a plant is its environment. The effects of the environment on the plant can be positive or negative. Just like animals, plants also respond to their environment. Phototropic responses are the most common responses. Phototropic responses involve the bending of growing stems toward light. The stems are phototropic because they grow towards the light. Growing the stems towards the light is obviously good since growing towards the light gives the plant greater exposure to light. A plant's growth will also be affected if another plant grows next to it. If a plant is alone, it will grow faster since it will not have any competition for light and water, but if there are two plants next to each other, they will have poorly and will not grow as much as the plant alone. Plant growth requires a large amount of energy, and plants get their energy from photosynthesis. Root growth determines the plant's ability to absorb necessary nutrients and water. Root growth depends on the leaves performing photosynthesis, because roots depend on the energy produced during the photosynthesis process. Roots only receive energy when they produce more energy than the plant uses. Temperature also affects plant growth. Cool temperatures reduce plant growth rates more than photosynthesis, which increases the amount of carbohydrates stored in a plant. There are also many other factors that affect plant growth, but the main factors are environment and temperature. Allelopathy is the word that refers to the positive and negative effects of one plant on another. The main factor affected by having only one place...... middle of paper ......as.ufl.edu/hs186>.Rayburn, Edward B. "Plant Growth and Development as a Basis of Forage Management" West Virginia University Extension Service. West Virginia University, December 1, 1993. Web. November 9, 2013. .Brenner, E., R. Stahlberg, S. Mancuso, J. Vivanco, F. Baluška and E. Van Volkenburgh. “Plant Behavior.” Signaling and plant behavior. University of Washington, January 1, 2006. Web. November 9, 2013. .R., Peter and Johnson G. “How Plants Grow in Response to Their Environment.” Biology. McGraw Hill, January 1, 2001. Web. November 9, 2013. .Schmidt, J. “Requirements for Plant Growth.” ACES Illinois. University of Illinois, April 30, 2012. Web. November 9. 2013. .