Germinated Onion Experiment

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How does varying intensity of light impact the rate of cell division of Allium fistulosum? My independent variable will be the amount of light the onions are exposed to ( 0 watts, 40 watts, 100 watts). My dependent variable will be the mitotic index of samples taken from each of the germinated onions. This will be calculated using root tip squashes.
Background Information:
Allium fistulosum, commonly called the spring onion, is an evergreen perennial. Underground bulbs are approximately the same thickness as the plant stem. They can grow to be between 2 and 3 feet tall. The end of the stalk is an umbel, a yellowish-white six-sepal flower. This plant blooms in May, requires full sun, and a medium amount of water.
The onions used in this experiment will be germinated. Germination is how a seed grows into a functioning plant. Several things are needed for germination to occur: appropriate temperature, oxygen, and water. The appropriate temperature encourages enzymatic activity, which increases the rate of reaction and thus allows for …show more content…

The A. fistulosum seeds will be planted and placed with access to varying degrees of light (0 watts, 40 watts, and 100 watts). The amount of light will inhibit or encourage cells to create ATP, which they will use to synthesise organic compounds, such as glucose for energy. As the light intensity increases, the rate of photosynthesis generally increases. The more nutrients that the cells are able to produce, the more growth the seeds exhibit.
This means that there should be more growth, or cell division. This allows for me to determine the mitotic index of the bulbs. The mitotic index is a ratio of cells in a sample that are in a phase of mitosis (prophase, metaphase, anaphase, telophase, or cytokinesis) to the total amount of cells in a sample. As light intensity is a factor that affects cell growth, the mitotic index should be

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