Using spinach leaves, we extracted the chloroplasts and observed the rate of photosynthesis in various concentrations of water. We created a control group in DI water, and two experimental groups- one in tap water with the other in salt water. The rate of the light-dependent reactions was monitored by comparing the absorbance of light in a spectrophotometer at 600 nanometers. As the DCPIP used in the experiment is reduced, the absorbance of light decreases. Similarly, the first stage of photosynthesis involves extraction of electrons from water by light energy for reduction. Knowing this, if the concentration of water increases within the plant cell, then the rate of the light-dependent reactions should increase as plants require water in the first step of photosynthesis. If our hypothesis is correct, the data would reveal that the chloroplasts exposed to tap water have a significantly lower absorbance over time than the chloroplasts exposed to salt water, where the concentration of H2O is less.
Comments
Suggestion
I would change the tense to make it sound more scientific. "chloroplasts were extracted and the rate of photosynthesis was observed in salt and tap water."
Punctuation
"...two experimental groups- one in tap water with the other in salt water."
I think you need to use a colon instead of a dash here, or otherwise rephrase the sentence.
You should define the
You should define the abbreviations used in your paragraph when you first introduce it.