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Does the direction of sunlight affect phototrophic movements?

Start by observing the living species around you. Ever wonder why a pollinator is attracted to a particular flower, or what would happen to predator species if a particular prey species is eliminated? If you were a scientist you could do an experiment to answer your question.

For this assignment, choose two non-human species that interact with each other, such as bees and flowers, or predator and prey species, or two species that compete. Or, you can consider the effect of an environmental factor on living non- human organisms, such as the effects of light or sound on plants or animals, or how food preference, or nutrient quantity / quality affect plants or animals. These are just a few examples. Your observations may lead you to many other types of questions about living organisms, their interactions, and requirements for life.

Start with an Introduction/Observation and move through the steps of the Scientific Method as outlined below. Your paper should follow this format. Remember, you don't have to actually do the experiment, just write what you would do to test your hypothesis.

Introduction: Describe your observation. Include background information about your observation that you have found using references. List and cite references using APA format.

Question: Ask a question about the observation that you have made.

Hypothesis: Write a statement that describes your explanation for the observation and question.

Prediction: What do you predict as outcomes (results) of this experiment? (An "If ... Then" Statement)

Controlled Experiment and Methods: Describe the experiment, variables to be held constant, variable to be tested, and controls. What data will be collected? Keep this simple and test only one variable at a time; holding the others constant.

Results: Give the results (data) for the experiment. This will be created (imagined) by you since you are not actually doing this experiment.

Conclusion / Discussion: Do you reject or accept the hypothesis based on the results? Discuss what this means in terms of the hypothesis, or need for additional experiments, or perhaps practical use of the results.

Tip: Use the logic incorporated in the scientific method. Remember that to conduct any experiment you need to make clear logical conclusions and deductions. Chapter 1 has good examples of experimental procedures.

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We observe growth movements among plants in our daily life. Growth movements are curvature movements caused by differential or unequal growth in plant organs, which results in their bending in the direction of a particular stimuli, for instance light. Such movements which are induced by external stimuli are called trophic movements. A trophic movement of plant organs in response to the source of light is known as Phototropism. The stem grows towards the direction of light, and is therefore said to exhibit positive phototropism. For instance, we have observed that shoot apices of Helianthus annus (Sunflower) plants exhibit phototropism by growing towards the direction of sunlight (Dr.Sharma, J.P.2006).

Dr.Sharma,J.P.(2006). Comprehensive laboratory manual in Biology(pp.169-170). New Delhi:Laxmi Publications Private Ltd.,

Question: Does the direction of sunlight affect phototrophic movements in plants?

Hypothesis: "The direction of sunlight plays an active role regarding phototrophic movements in plants."

Prediction: "If a plant is placed in a heliotropic chamber or card board box with a hole on ...

Solution Summary

This solution provides an introduction, question, hypothesis, prediction, controlled experiment and methods, results and conclusion in 700 words with one reference.