The hypothesis was partially correct.
The plants that grew under sunlight were the healthiest, but they
didn’t grow the fastest. Sunlight
is made up of the perfect balance of light colours.
On the downside, these plants were the shortest.
Yet they were the darkest and had the most number of leaves.
Fluorescent light was the second best choice of lighting for the two
types of bean plants. Plants that
grew under the fluorescent tube were the second highest, second darkest, and had
the second most number of leaves. One
should note that fluorescent lighting is also more efficient that incandescent
lighting. Incandescent lighting is the worst of the three types of
lighting that were used. Even
though the plants that grew under incandescent light were the tallest, they had
the least number of leaves, and were the least dark.
While the experiments were conducted, plants that grew under sunlight
were the shortest yet the healthiest. They
were short because they grew slower than the other plants. This occurred because the plants that grew under sunlight
received light with lower levels of light quantity, i.e. light intensity.
Another factor that accounted for the slow growth rate of these plants
was the temperature. Increasing the temperature will, up to a certain point,
increase the plant’s capacity of photosynthetic activity. Since sunlight already contributes to the temperature of the
earth, it does not raise room temperature.
Given time, these plants would have been the tallest of the different
types of plants too.
The plants that grew under fluorescent light grew the second best. They weren’t as dark as the plants that grew under sunlight
but darker than the plants that grew under the incandescent bulb.
It was the second tallest, had the second most number of leaves, and the
second darkest. It had many leaves
because cool fluorescent tubes produce a significant amount of light form the
blue/indigo end of spectrum. Unfortunately, fluorescent tubes do produce some waste heat,
which contributed to a faster rate of evaporation. It was noticed that the cotton that the seeds were planted in
was usually dry when it was watering time.
The piece of cotton that was placed under sunlight was usually damp at
the end of the day. On the other
hand, the piece of cotton that was placed under an incandescent tube was
extremely dry, without the tiniest bit of moisture in it.
Of all the types of lighting used, incandescent is, with no doubt, the
very worst. The plants that grew
under the incandescent bulb were the least healthy.
They were a pale white-green colour, signifying a low number of
chlorophyll cells. To top it off,
incandescent bulbs are highly inefficient; they produce a considerable amount of
waste heat and very little light for the amount of energy that is needed to make
them run. The plants that grew
under the incandescent bulb grew the fastest because of the increase of
temperature, which the incandescent light bulb created.
Light that comes from incandescent light bulbs has very little light from
the blue/indigo end of the spectrum, which encourages foliage growth.
This is why the plants that grew under the incandescent bulb had so few
leaves. Nearing the end of the
experiment, the heat that the incandescent bulb produced burned the edges of
some of the stems and leaves.