UNIT+3-+CELL+ENERGY

__Summary: __ In this Unit, you will learn about the processes of photosynthesis and cellular respiration. Photosynthesis occurs in plants, while cellular respiration occurs in animals. Both of these processes produce ATP which makes energy for the cells. Photosynthesis occurs in two steps: light reactions and Calvin cycle. Cellular respiration occurs in three steps: glycolysis, Krebs cycle and Electron Transport Chain (ETC). However, cells only go to the ETC step if oxygen is present. If oxygen is not present, fermentation occurs. Either way, the cells make ATP and use it for energy. 

__Objectives: __ • Look into the process of photosynthesis and how it works in plant cells • Examine the process of cellular respiration and how it occurs in animal cells 

** ATP ** - adenosine triphosphate; high energy molecule; has three phosphate groups attached ** Cellular respiration ** - process by which organisms convert glucose to energy, usually using oxygen and glucose to produce ATP, carbon dioxide, and water ** Chloroplasts ** - organelles found only in plants that absorb sunlight and use it to drive the synthesis of organic compounds from carbon dioxide and water ** Krebs Cycle ** - chemical cycle involving eight steps that completes the metabolic breakdown of glucose molecules to carbon dioxide; occurs within the mitochondrion; the second major stage in cellular respiration ** Mitochondria ** - organelles in eukaryotic cells that are the site of cellular respiration ** Stroma ** - fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water  ** Symbiosis ** - relationship between organisms of two different species that live together in direct contact  ** Thylakoid ** - membrane sac inside the chloroplast, used to convert light energy to chemical energy 
 * __ Vocabulary __** :
 * ADP ** - adenosine diphosphate; low energy molecule; has two phosphate groups attached to the adenine base and ribose sugar 
 * Calvin Cycle ** - second of two major stages in photosynthesis (following the light reactions) involving carbon dioxide fixation and reduction of the fixed carbon into carbohydrate 
 * Chlorophyll ** - green pigment found in most plants 
 * Electron Transport Chain (ETC)- ** sequence of electron carrier molecules that shuttle electrons during the reactions that release energy used to make ATP
 * Epidermis ** - dermal tissue system in plants
 * Glycolysis ** - splitting of glucose into pyruvate; Serves as the starting point for fermentation or aerobic respiration
 * Glucose ** - monosaccharide sugar which is a principal source of energy for most living things
 * Granum ** - stacked portion of the thylakoid membrane in the chloroplast; function in the light reactions of photosynthesis 
 * Light reaction ** - steps in photosynthesis that occur on the thylakoid membranes of the chloroplast and that convert solar energy to the chemical energy of ATP evolving oxygen in the process 
 * Photosynthesis ** - process by which cells containing chlorophyll combine light energy with water and carbon dioxide to produce oxygen
 * Pyruvic acid ** - acid formed as an important intermediate in metabolism or fermentation
 * Stoma ** - microscopic pore surrounded by guard cells in the epidermis of leaves and stems that allows gas exchange 