Name: Melvin G. Abramson
SCI 115 – Essentials of Biology
Professor: Casey Bethel
Date: May 1st, 2012
Photosynthesis is the progression of translating light energy to chemical energy and storing it in the acquaintance of sugar. This process occurs in plants and some algae. Photosynthesis takes place in the chloroplasts, distinctively using chlorophyll, the green pigment implicated in photosynthesis. Photosynthesis mainly transpires in plant leaves. The two parts to photosynthesis are light and dark reactions. The light reaction comes about in the thylakoid membrane and then switches light energy to chemical energy. Each of these differently-colored pigments can attract a slightly different color of light and pass its energy to the central chlorophyll molecule to do photosynthesis. The energy harvested via the light reaction is stored by structuring a chemical called ATP (adenosine triphosphate), a compound employed by cells for energy storage. This molecule is very similar to the building blocks for our DNA. The dark reaction takes place in the stroma within the chloroplast, and converts CO2 to sugar. This reaction does not really require light but it do necessitate the products of the light reaction (ATP and another chemical called NADPH). The dark reaction involves a cycle called the Calvin cycle in which CO2 and energy from ATP are used to form sugar. Carbon dioxide and water are the two reactants while Carbohydrates and oxygen are the products.
The most resourceful way for cells to yield energy stored in food is through cellular respiration, a catabolic conduit for the production of adenosine triphosphate (ATP). ATP, a high energy molecule, is expended by working cells. Cellular respiration arises in both the eukaryotic and prokaryotic cells. It has three focal stages: glycolysis, the citric acid cycle, and electron transport. Glucose is
References: Campbell, Neil A., Lawrence G. Mitchell, Jane B. Reece. 1999. Biology, 5th Ed. Benjamin/Cummings Publ. Co., Inc. Menlo Park, CA. (plus earlier editions) Campbell, Neil A., Lawrence G. Mitchell, Jane B. Reece. 1999. Biology: Concepts and Connections, 3rd Ed. Benjamin/Cummings Publ. Co., Inc. Menlo Park, CA. (plus earlier editions) Essentials of Biology, 2009 Custom Edition