Photosynthesis & Respiration Intro Video: http://www.neok12.com/php/watch.php?v=zX787d585f475a015b5c7c06&t=Photosynthesis

(Photosynthesis and Respiration) Cell Energy (Photosynthesis and Respiration) Energy: Energy for living things comes from food. Originally, the energy in food comes from the sun.

Organisms that use light energy from the sun to produce food—autotrophs (auto = self) Ex: plants and some microorganisms (some bacteria and protists)

Organisms that CANNOT use the sun’s energy to make food—heterotrophs - must eat their food Ex: animals and most microorganisms

Cells usable source of energy is called ATP Cell Energy: Cells usable source of energy is called ATP ATP stands for adenosine triphosphate Adenine Ribose 3 Phosphate groups

ADP stands for adenosine diphosphate Adenine Ribose 2 Phosphate groups

All energy is stored in the bonds of compounds—breaking the bond releases the energy When the cell has energy available it can store this energy by adding a phosphate group to ADP, producing ATP

ATP is converted into ADP by breaking the bond between the second and third phosphate groups and releasing energy for cellular processes.

Photosynthesis: Photosynthesis is the process by which the energy of sunlight is converted into the chemical energy of glucose

Photosynthesis occurs in the chloroplasts of plants

Light absorbing compound is a pigment pigments absorb some wavelengths of light and reflect others the color our eyes see is the color that the pigment reflects

Chlorophyll is the pigment inside the chloroplast the absorbs light for photosynthesis As the chlorophyll in leaves decays in the autumn, the green color fades and is replaced by the oranges and reds of carotenoids.

General formula for photosynthesis: sunlight carbon dioxide + water —> glucose + oxygen sunlight 6CO2 + 6H2O —> C6H12O6 + 6O2

Reactants Diagram H2O CO2 Light Chloroplast C6H12O6 Glucose O2 NADP ADP + P Light Dependent Reaction Calvin Cycle ATP NADPH Chloroplast C6H12O6 Glucose O2 Products

Light Reaction Takes place in the thylakoid membrane (contains chlorophyll) Reactants needed for the light reaction: Water, Light, ADP, NADP Products made from light reaction and USED in dark reaction: ATP energy to make sugar NADPH supplies e- and H to make C6H12O6 Oxygen is released into the air

Dark Reaction - Calvin Cycle Takes place in the stroma Reactants needed for the dark reaction: CO2, ATP, NADPH Products made from the dark reaction used in light reaction are: ADP returned to the light reaction to make more ATP NADPreturns to the light reaction to pick up more electrons and Hydrogens Glucose is made in the dark reaction for use throughout the organism.

Summary: Light Reaction—H2O is broken down and light energy is stored temporarily in ATP and NADPH. Oxygen released. Calvin Cycle—energy is transferred from ATP and NADPH to the organic compound glucose

Location Reactants Products Release H2O Light Reaction thylakoid Light ADP and NADP from dark reaction ATP – energy to make sugar NADPH – electrons and Hydrogen to make glucose O2 to the air Dark Reaction – Calvin Cycle stroma CO2 ATP and NADPH from light reaction ADP and NADP back to light reaction GLUCOSE

Video - photosynthesis http://www.goldiesroom.org/Multimedia/Movie_Clips/05%20Nutrition/Photosynthesis%20Review.wmv

Cellular Respiration Process where energy of glucose is released in the cell to be used for life processes (movement, breathing, blood circulation, etc…)

Respiration occurs in ALL cells Takes place in the mitochondria Can take place either with or without oxygen present.

Glucose Glycolysis ATP Pyruvic Acid Aerobic Fermentation Respiration No Oxygen Oxygen Aerobic Respiration Fermentation (anaerobic) Lactic Acid Ethyl Alcohol ATP

Aerobic Respiration: Makes 38 ATP requires oxygen Formula C6H12O6 + 6O2 6 CO2 + 6H2O + 38 ATP glucose + oxygen carbon dioxide + water + energy Human cells contain a specialized structure – the mitochondrion – that generates energy.

Intro video - respiration http://www.goldiesroom.org/Multimedia/Movie_Clips/07%20Respiration/Aerobic%20Review.wmv

STEP 1: Glycolysis First pathway of respiration - ALL organisms perform this Takes place in the cytoplasm on enzymes Splits glucose in half to form pyruvic acid or pyrates Gives off enough energy to make 2 ATP

STEP 3: Electron Transport Chain STEP 2: Krebs Cycle pyruvic acid is broken down into carbon dioxide Occurs in matrix of mitochondria STEP 3: Electron Transport Chain electrons from Krebs Cycle converts ADP into ATP Occurs along inner membrane of mitochondria

Electron Transport Chain Diagram - Cellular Respiration Electrons carried in NADH Mitochondria In Cytoplasm electrons carried in NADH Krebs Cycle Electron Transport Chain Glucose Glycolysis 2 2 34

Video on aerobic respiration: http://videos.howstuffworks.com/discovery/29543-assignment-discovery-cellular-respiration-video.htm

Anaerobic Respiration or Fermentation: pathway organisms use when no oxygen is available to the cell Mostly unicellular organisms (low energy requirement) Goes through glycolysis and makes 2 ATP (in cytoplasm) 2 kinds: Alcoholic and Lactic Acid

Lactic Acid Fermentation pyruvic acid lactic acid+carbon dioxide Performed by muscle cells Lactic acid is produced in the muscles during rapid exercise when the body cannot supply enough oxygen to the tissues—causes burning sensation in muscles

Lactic Acid Fermentation

Alcohol fermentation Pyruvic ethyl alcohol+carbon dioxide acid occurs in bacteria and yeast Process used by baking and brewing industry yeast produces CO2 gas during fermentation to make dough rise and gives bread its holes

CYCLE! Photosynthesis and Respiration Products of one reaction are the reactants of the other (and vice versa) CYCLE!

Ecological Level Energy Flow: Producers photosynthesize and provide glucose for consumers Carbon Cycle: Producers remove CO2 from atmosphere while consumer replaces CO2 during respiration Water Cycle: Producers take water out of ecosystem and consumers produce water during respiration (also O2 removed by producer and returned by consumer)

Importance of ATP! 1. ALL organisms release ATP from break down of glucose during cellular respiration 2. ATP powers the activities of the cell and allows living things to do work 3. ATP/ADP is cycle that releases/stores energy for cell processes 4. ATP is used to actively transport material across the cell membrane

Cells require a constant source of energy for life processes but keep only a small amount of ATP on hand. Cells can regenerate ATP as needed by using the energy stored in foods like glucose. The energy stored in glucose by photosynthesis is released by cellular respiration and repackaged into the energy of ATP.