Photosynthesis Energy Case Study

Photosynthesis is the process by which plants convert Carbon dioxide and solar energy into a sugar called glucose; this glucose is the plants main food source and oxygen is the byproduct of this process. The photosynthesis process occurs mainly in the chloroplasts in the leaves of plants as they absorb the carbon dioxide through adjustable pores called stomata. Also located inside of the leaf are the mesophyll; the mesophyll contain much of the chloroplasts that the plant uses for photosynthesis, as a result much of this process takes place here. Delving deeper, one finds organelles known as stroma - a double outer layered type of organelle that when combined form chloroplasts - here is where the reaction that uses carbon dioxide takes place. Embedded in the stroma are thykaloids; these disc shaped sacs are where the chemical reaction of photosynthesis that uses light take place.

As light strikes the plants leaves, a molecule within the chloroplasts known as chlorophyll absorbs it and runs it down what could be considered a conveyer belt of sorts until it reaches the reaction center. Once at the reaction center the light energy effectively kicks an electron out and to the primary electron receptor. In order to keep the operation fueled as electrons are constantly be bumped from the reaction center the plant must have water which is split by a special enzyme freeing up the electrons needed to keep the lights on in the reaction center so-to-speak; for every two water molecules that are split up there is one oxygen molecule produced(T. Audesirk, G. Audesirk & B. Byers 2011).

Both cellular respiration and photosynthesis rely involve the exchanging of gases such as carbon dioxide and oxygen to transform energy by either storing or releasing it. The cellular respiration process begins when pyruvate is broken down to be transported to what is known as the mitochondrial matrix where all of the necessary enzymes are created; when this split occurs carbon dioxide is released from the resulting energy exchange as well as acetyl CoA (coenzyme A). Acetyl CoA is combined with a four carbon molecule to release coenzyme A (a citrate composed of six carbons) in the process known as the Krebs, or the citric acid cycle. As each acetyl group is broken down to form coenzyme A, an ATP is created along with NADH(3) and FADH2 - a derivative of flavin adenine dinucleotide (FAD) that picks up two energy electrons and an H+ during the Krebs cycle (Audesirk et al. 2011). High energy electrons that were gained during glycolosis and the Krebs cycle are released into the electron transport chain (ETC). As these electrons make their way down the ETC, hydrogen is pumped across the inner membrane combining at the end of the ETC with oxygen, and the electrons now void of energy to form water.

The hydrogen flowing across the internal membrane space in the mitochondrial matrix through ATP-synthesizing enzymes. This process creates ATP from ADP which provides