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PHOTOSYNTHESIS & CELLULAR RESPIRATION. ENERGY IN A CELL!!. Your body requires energy in order to function…from your heart beating to intense workouts. Energy is essential to LIFE!!. ATP'S. Your body stores energy in a molecule called ATP’s (adenosine triphosphate) - PowerPoint PPT Presentation



  • ENERGY IN A CELL!!Your body requires energy in order to functionfrom your heart beating to intense workouts. Energy is essential to LIFE!!

  • Your body stores energy in a molecule called ATPs (adenosine triphosphate)This is a quick source of energy for any organelle in the cell that needs it.

  • The energy inside an ATP molecule is released when it loses a phosphate and becomes ADP (adenosine diphosphate)

  • ADP is like a partially charged battery while ATP is a fully charged battery.

  • Chlorophyll, more like borophyll!

    Sorry, just had to make an effort to take away the chance for the smart elacks that will be lucky to make a C in this class to use this line and get a laugh. Now they can pay attention for the 5 minutes their little pea-size brain will allow them

  • PHOTOSYNTHESISPhotosynthesis is a process in which solar energy in the form of light is converted into chemical energy within carbohydrate molecules.


    6 CO2 + 6 H2O + light ---> C6H12O6 + 6 O2

  • PHOTOSYNTHESISPhotosynthesis occurs in organelles, present in green plants and certain algae, called Chloroplasts.

  • Chloroplast

  • CHLORPLASTA chloroplast is filled with stacks of membrane sacs called thylakoids.Thylakoids are stacked in columns of grana.


  • A chloroplast usually has dozens of granum. They are suspended in a fluid matrix called the stroma.

    Chlorophyll molecules are embedded in the thylakoid membranes. Chloroplast

  • This is a close up version of a chloroplast in a leaf.

  • These chloroplasts contain the green pigment called chlorophyll. Chloroplast

  • CHLOROPHYLL Chlorophyll- pigment found in plants it will absorb red, blue, and violet better than other colors. Green light is primarily reflected so most leaves appear green to us.There are two types of chlorophyll a and b

  • CHLOROPHYLLNotice how Chlorophyll a absorbs light mostly in the blue-violet and red regions.Chlorphyll b absorbs light in the blue and red regions more.

  • CHLOROPHYLLBecause light is a form of energy, any compound that absorbs light also absorbs the energy in that light.When chlorophyll absorbs light much of the energy is transferred directly to electrons in the chlorophyll molecule, raising the energy available in these electrons.

  • CHLOROPHYLLElectrons carriers are seen throughout the Photosynthesis concept.They are compounds that can accept high-energy electrons and transfer them along with most of their energy to another molecule. NADP+ NADPHADP ATP

  • 2 REACTIONS OF PHOTOSYNTHESISPhotosynthesis involves 2 reactions:1. Light Reaction.2. Calvin Cycle.

    (Also called Light Independent Reaction and Dark Reaction.)

  • STOMATAThe stomata are important for the exchange of gases by diffusion between the outside air and intercellular spaces for respiration and also for the evaporation of water by transpiration.

  • Notice how the equation for photosynthesis relates to the reactions shown in the diagram below. 6CO2 + 6H2O + Energy C6H12O6 + 6O2

  • Melvin Calvin (1911 1997)Again, this is also known as the Calvin CycleNamed after the American scientist Melvin Calvin, who worked out the details of this cycle in 1948Won Nobel Prize in chemistry in 1961


  • CELLULAR RESPIRATIONC6H12O6 + 6O2 ---> 6 CO2 + 6 H2O + Energy

  • CELLULAR RESPIRATIONThe process by which living organisms obtain energy from the bonds of food.There are two important ways the cells can harvest energy from food.cellular respiration and fermentation

  • AEROBIC RESP.Aerobic respiration occurs when oxygen is present. Aerobic respiration produces a relatively large amount of energy (ATP)

  • ANAEROBIC RESP.Anaerobic respiration occurs when oxygen is not present. Produces few ATPsAnaerobic respiration may also be called fermentation.

  • WHAT IS ATP?(adenosine triphosphate) compound that contains 3 high energy phosphate bonds and is an important source of energy for cells

  • ATP

  • CELLULAR RESPIRATIONCellular Respiration consists of 3 major stages: Glycolysis Krebs CycleElectron Transport Chain..(ETC)

  • GLYCOLYSISThey (CR and Fermentation) both start with the Glycolysis The 1st stage of cellular respiration. Occurs in the cytoplasm of the cell.Occurs in both aerobic and anaerobic conditions.BUT Does NOT require oxygen

  • GLYCOLSISThis metabolic pathway breaks down glucose (produced in photosynthesis) to 2 molecules of pyruvate There is a net gain of 2 ATP molecules.

  • KREBS CYCLEAlso known as citric acid cycle2nd phase of aerobic respirationOccurs in the Mitochondria

  • Kreb CycleThe process of Kreb Cycle is essentially removing carbon dioxide, getting out energy in the form of ATP, NADH and FADH2, and lastly regenerating the cycle.

  • Kreb CycleThe Kreb Cycle has a by-product of CO2Energy is carried to the ETC by two electron carriers.NADH and FADH2A total of two ATPs are produces through the Kreb Cycle

  • Hans Krebs (1900 1981)Krebs cycle named after Hans Krebs, biochemist who demonstrated its existenceBorn in Germany, son of Jewish physician, forced to leave Nazi Germany in 1933Spent rest of life in Great BritainDiscoveries were initially rejectedWon Nobel Prize in 1953 in medicine & physiology

  • ELECTRON TRANSPORT CHAIN (ETC)Last stage of cellular respirationSeries of Reactions in which an electron is passed from one molecule to another to produce energy for synthesis of ATP

  • ETCThe electrons move down the chain along the inner membrane of the mitochondriaThey are carried by NADH and FADH2 (carrier molecules)

  • ETCAs hydrogen ions move across the channels in the membrane to the matrix, they release energy that is used by an enzyme to make ATPOxygen is the final electron acceptor.Water is formed in this is a by-product

  • ETCResults in ETC the electron transport chain produces 32 molecules of ATP

    With H2O being a by-productO2 enters the ETC

  • Cellular RespirationTOTAL ATP PRODUCTION IN CELLULAR RESPIRATION Glycolysis, 2 ATPs Krebs, 2 ATPs + ETC, 32 ATPs = 36 ATPs TOTAL

  • OVERVIEWGlycolysis is anaerobicWhen oxygen is present, then the previously discussed pathway (Krebs cycle, ETC) is takenWhen oxygen is NOT present, a different pathway is taken, fermentation

  • CELLULAR RESPIRATIONA car and our bodies are similar in the fact that the mitochondria is our bodies engine that burns sugar for fuel. The exhaust would be H2O and CO2

  • FERMENTATIONFermentation releases energy from food molecules in the absence of oxygen.

  • The Process of FermentationGlucose is broken down into pyruvate during glycolysisPyruvate is then broken down into ethyl alcohol or lactic acidOnly results in 2 ATP molecules (vs. 36 from aerobic)

  • ALCOHOLIC FERMENTATIONMost common type of fermentation is yeast cells converting pyruvate into ethyl alcoholFermentation by itself is able to produce liquids that are about 15% alcoholThe same process enables yeast cells to convert the sugar in dough to ethyl alcohol & carbon dioxide

  • FERMENTATIONBakers use alcoholic fermentation of yeast to make breadsAs yeast ferments, it causes dough to rise & create the bubbles that are present in bread

  • FERMENTATIONAs the dough bakes, yeast cells die and the alcohol they have made evaporates

  • FERMENTATIONAlso used to make wine, beer, and ethanol added to gasoline

  • LACTIC ACID FERMENTATIONOccurs in muscle cells when they use up all the available oxygenMuscle cells feel fatigued and sore b/c lactic acid forms when oxygen is NOT present

  • LACTIC ACIDMost lactic acid made in muscles diffuses into bloodstream, then to liver, where it is converted back to pyruvate, which enters the aerobic respiration processYogurt, cheeses, rye bread, pickles, sauerkraut, and olives are lactic acid products

  • LACTIC ACIDYogurt, cheeses, rye bread, pickles, sauerkraut, and olives are lactic acid products