How is Plant Growth Affected by Sunlight?
Introduction
Background information
Sunlight is essential to plants. Plants in dark room tend to grow towards sunlight. When they lack sunlight, photosynthesis does not take place causing them to wither and die.
Photosynthesis takes place in the leaves of a plant. In plant leaves, there are organelles called chloroplast. They form site for photosynthesis process. They are very many in a leaf.
Within chloroplast, there is chlorophyll, that are usually green in color, hence the green coloration in plants.
Plants require air, water and sunlight for photosynthesis to occur. Air goes inside the leaf via stomata, water is absorbed from the ground through the roots and sunlight is absorbed by the chloroplasts in the leaves.
Chemical reaction takes place in chloroplast once all these factors are present. In the reaction, sunlight causes water and carbon dioxide from air to combine, resulting to carbohydrates.
Carbohydrates are what plants utilize as food to grow and live.
Observation
Our houseplants leaned towards the wall where there were sun rays reflected on at times. However, they withered and died after a few days
Problem
Why did the houseplant wither and die?
Hypothesis
Without sunlight, carbohydrates can’t be formed. The chemical reaction will therefore not take place leading to lack of food for plant.
Absence of one main ingredient prevents photosynthesis from taking place.
Plants wither and die without sunlight.
Procedure
Equipment used and the purpose of their use
Two plants and a box are used. One plant, Plant A is the control, while the other, Plant B will be tested on using the box.
List the procedure
In step one, plant A was set up outside the house where sunlight was sufficient
In step two, plant B was put inside the box.
In step three, the set ups were left undisturbed and monitored for a week.
Results
After one week had elapsed, plant A grew healthy while plant B withered and died.
Discussion
Support the hypothesis
Lack of sunlight caused plant B to wither and die, while plant A grew well
Explanation of the result
Since there was no sunlight in plant B, which was inside the closed box. It therefore lacked all the required ingredients for photosynthesis, causing photosynthesis not take place. Plant A showed perfect growth as it had all the factor required for photosynthesis to occur and produce carbohydrates.
Conclusion
This proves that for a chemical reaction to take place in plants so that carbohydrate (food) can be made, sunlight is required for the reaction. Without sunlight plants cannot grow well, and will eventually die.
