How Does Light Effect the Growth of a Lima Bean?

Background research paper

How does light effect the growth of a lima bean?

The purpose of this experiment is to see if/ how light affects the growth of lima bean seedlings. Lima beans were placed in three different places; where in one place the light is natural, and another, its power generated and controlled. Two lima beans were put in the cabinet, with no light, two lima beans were left outside; where they were exposed to natural light, and two lima beans were placed under a heat lamp; where they were exposed to a constant light and heat. The lima beans are observed and data is recorded. Height and growth rate are recorded for the experiment.

The original hypothesis is "if the lima beans were placed in three completely different light variations (heat lamp, outside, and cabinet) then the lima beans that were placed outside will grow the fastest because carbon dioxide; which fills the air outside, plays a key role in the growth and development of plants". Germination is one way to give evidence for the hypothesis and the assumption for the results of the experiment. One thing needed to know when growing lima beans is what Germination is. Beans, like all other seeds, need moisture to germinate. As the seedling absorbs water from the soil, chemical reactions take place within the seed. These reactions tell enzymes to start using the seed's stored energy to produce primary structures for the seedling. Sunlight is not needed for any of these processes. That is why the hypothesis shows that the lima beans growing outside will grow fastest. Germination proves that a plant does not need constant sunlight to grow. The first structure that emerges from the germinated bean seed is a primary root called a radicle. The radicle extends into the soil. As it does so, a hook forms where the radicle attaches to the bean seed. Again, no sunlight is needed for this to happen. The weather is more at random in Washington at this time of year; some rain, snow, sun which is why the Lima beans outside will grow fastest. The outdoors has every element that is used and needed to develop a plant at its quickest.

In this project the independent variable is the type of light being used which is also being the cause of lima bean growth. The lighting that is used while growing the lima beans is different for each plant because there are lima beans being grown outside, in a cabinet, and under a heat lamp. The dependent variable in this experiment is the height of the plants, which is constantly changing or will change over time as the lima beans grow. The controlled variables are the amount of soil being used (1 cup), the amount of seeds put into each pot (two), and the amount of water being given to each pot (1/2 cup). Soil, water, and the amount of beans are the variables that are not changed in the experiment.

When talking about the growth rate of Lima