The Affects of Certain Colors on the Growth of a Plant

Abstract

The experiment examined the affects of certain colors on the growth of a plant. The experiment was comprised of two different sets of plants, one served as the control, while the second served as the experimental group. The control group was the set without colored film covering it. The control group was in normal light. The experimental group was the set that was placed beneath a green film covering. Both sets of plants required water daily to obtain the most accurate results. Both sets of plants also had to be placed under the same type of light, so that both sets would have parallel results. This resulted in the control group attaining an increased and more consistent growth pattern. However, the experimental group resulted in a decreased and more inconsistent growth pattern. In the end, it can be concluded that most plants contain a significant majority of the pigment chlorophyll. Plants that contain mostly chlorophyll will not absorb the green light. The green light will be rejected by the plant which without the other light getting through, it will hinder photosynthesis.

Introduction

In order to gain a better understanding of why this lab was performed, one must gain a general understanding, as well as background information in relationship to the lab that was performed. The importance of understanding the pigments is integral. "Pigments are molecules that absorb wavelengths in the visible region of the [color] spectrum" (Purves, 140). Pigments absorb the given light when a ray of white light contacts the pigment. The light that is not absorbed is reflected. This is how the various colors are made visible, the reflection of the light. For example, if the dominant pigments in a plant are green, then the plant will absorb light from the blue, violet, and red regions of the spectrum. The green pigments are then reflected allowing the plant to be green. Also, pigments are very closely related to photosynthesis. "The leaves use a green pigment, chlorophyll, to aid in the photosynthesis." The different wavelengths of light effect photosynthesis in different ways. This is illustrated by the action spectrum. The action spectrum shows that most photosynthetic activity occurs in the blue-violet and orange-red areas of the spectrum. So, if blue-violet and orange-red light is absorbed, then green light is reflected and appears as the primary plant color. The pigment combinations in plants determine which wavelengths of light can be utilized most effectively in photosynthesis. The purpose of this lab was to help students gain a firmer grasp on how different colors of light affect the growth of plants. The lab was performed to determine whether a particular plant type would exceed normal growth if placed under a green film covering, as opposed to without a film covering. Prior to the experiment, all plants that were being used in the experiment were observed and said to be healthy with relation to each other.

Hypothesis: The plants plated under the green film covering will not grow.

Null Hypothesis: The plants placed under the green film covering will grow.

Materials

In this lab experiment the materials that were used were a quad Styrofoam unit, sixteen seed pods, potting soil, and a sheet of green film covering, a scalpel, a beaker, plastic container, water, and a light producing unit.

Procedure

In the experiment, each of the four quadrants of the Styrofoam unit was first filled with potting soil. Followed by an indention being made in the soil to place the seed pods in each individual quadrant. A total of sixteen seed pods were used. Four seed pods were used in each quadrant of the Styrofoam unit. After placement the seed pods were then back filled thoroughly with potting soil. The scalpel was used to divide the unit into two separate units. Then a beaker was filled with water and the two separate units were lightly watered. A sheet of green film covering was then placed over the two experimental quadrants. In order to secure the film over the plants, a stapler was used. Both sets (with and without film) were then placed on a container that was partially filled with water. The container with the plants was then placed in the light unit that facilitated the production of the light needed for the experiment.

Results

From the control group, plant one under normal light showed growth on