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Fermentation 1 Slide 2 Background Living cells vary in shape & size, although most are microscopic (10 -6 m). Cells perform an assortment of processes to sustain life. We will study/have studied: Transport, Photosynthesis, Respiration, Fermentation, & Division. Each process serves a specific function for the cell. 2 Slide 3 Photosynthesis Light energy used to make chemical energy (glucose) Reactants: Water + Carbon dioxide Products: Glucose + Oxygen 3 Slide 4 Respiration Glucose (C 6 H 12 O 6 ) is burned for energy, in the presence of Oxygen (2 stages). Cytoplasm first Mitochondria second Reactants: Glucose + Oxygen Products: Carbon dioxide + Water 4 Slide 5 Turn & Talk to complete this frame: Photosynthesis Respiration 5 Slide 6 Fermentation This process occurs with little to no Oxygen available to the cell (in cytoplasm). Less energy generated than respiration. Many byproducts of fermentation are enjoyed by humans (see photo). 6 Slide 7 Fermentation ( without O 2 ) Alcoholic Products: Alcohol CO 2 Small amount of energy Important to bakers & brewers. Other applications: antifreeze, antiseptics, fuels, preservatives & solvents. Lactic Acid Products: Lactic acid (C 3 H 6 O 3 ) CO 2 Small amount of energy Present in sore/painful muscle tissue. This acid is also found in sour milk products, as a result of Lactic acid producing bacteria. 7 Slide 8 Turn & Talk to Complete: 8 Respiration Fermentation Slide 9 How cells get food... Autotroph aka producer, or maker. self-feeder An organism with cells capable of making food. Heterotroph aka consumer, eater, or hunter. other-feeder An organism which must eat other cells to gain nourishment. 9 Slide 10 Terms to know Must Know: Autotroph Chlorophyll Chloroplast Energy Fermentation Glucose Heterotroph Mitochondria Photosynthesis Products Raw materials (Reactants) Respiration Yields ( ) Challenge: Aerobic Anaerobic ATP Citric Acid Cycle (Krebs) Endergonic Exergonic NAD NADPH Slide 11 Challenge (optional) Adenosine tri-phosphate (ATP) synthesis is driven by a Hydrogen ion gradient known as the proton motive force (PMF). The PMF is a surplus of hydrogen ions, or [H+], trapped in between the two membranes of the mitochondrion in a region called the intermembrane compartment. The [H+] are only able to return to the matrix through a hydrogen ion channel (pump). When they do so, they are moving from an area of high [H+] concentration, through the channel, into the matrix, where the [H+] concentration is lower. This process is called chemiosmosis. As they make this move, an ATP-synthesizing enzyme converts Adenosine di- phosphate (ADP) to Adenosine tri-phosphate (ATP). So, the true chemical energy lies in that 3 rd bond from ADP to ATP. It is the breaking & re-assembling of this molecule that releases energy in the cell for use. 11 Slide 12 Cell Division Mitosis: nuclear cell division (body cells) Meiosis: sex cell division (sperm & egg) 12 Slide 13 Transport Q: How do cells get materials in & out? Active Energy required. ATP Ex: Facilitated diffusion Membrane proteins assist entry & exit. Passive No energy required. Diffusion: materials spread from high concentration to low. Osmosis: The diffusion of water. 13 Slide 14 14