All living plants produce energy in their cells through the process of photosynthesis. This process takes place in the chloroplasts of plant cells, and consists of several chemical reactions that allow plants to harvest sunlight and produce carbohydrate molecules. This experiment used two model systems to study the effects of light on photosynthesis rates. The chloroplasts of spinach, also known as Spinacia oleracea, was the first model system studied. Spinach chloroplasts have been used as a model system in several experiments, including being used to study chloroplast DNA synthesis in relation to chloroplast growth and replication (Possingham,1976). The chloroplasts of kale, also known as Brassica oleracea, was the second model system used in this experiment. Kale is not widely used in laboratories when studying chloroplasts, but has been used as a model system in experiments involving the changes of chlorophyll pigment concentrations (Lefsurd, 2007).
Comments
A little more description
I thought that this was a solid paragraph, but I think you could use a little more elaboration. For instance, when you mentioned that spinach is not commonly used as a model organism you should briefly explain why.
Introduce photosynthesis more
I am in agreement that more description could be used. Given that this is the introduction, the process of photosynthesis could be expaneded on. Instead of saying it occurs in chloroplasts and consists of multiple chemical reactions, you could incorporate that there are light and dark reactions in the thylakoid and stroma of the chloroplast.