Presentation on theme: "CAPTURING ENERGY Chapter 6"— Presentation transcript:
1CAPTURING ENERGY Chapter 6 PHOTOSYNTHESISCAPTURING ENERGYChapter 6
2ENERGYAutotrophs – Organisms that make their own food from inorganic substances and energy (ATP).Use photosynthesis – converting light energy into chemical energyStore chemical energy as organic compounds (like carbohydrates)EX: plants, algae, and some bacteria
3PHOTOSYNTHESIS 6CO2+6H2O+light C6H12O6+6O2 A biochemical pathway that involves a complex series of chemical reactionsThe product of this reaction is consumed in the next reactionProcess supports virtually all life on Earth
4Understanding Photosynthesis 1. Jan Van Helmont (1600’s) – set up an experiment to understand how a small seed grew to a large treeConcluded that plants need water to grow.2. Joseph Priestly (1771) – set up an experiment with a candle…he discovered a candle in a jar died out but a candle in a jar with a plant continued burning.3. Jan Ingenhousz (1779)– found that the plant/candle experiment only worked when the plant was exposed to sunlightConcluded: light is necessary for plants to produce oxygen
5The Nature of LightVisible Spectrum – the separation of white light into different colors (wavelengths)PIGMENT – a molecule that absorbs certain wavelengths of light and reflects or transmits others
6Chloroplasts- organelle that contains chlorophyll Chloroplasts- organelle that contains chlorophyll and other pigments; site of photosynthesisContains:Thylakoids – disk-shaped structures that contain photosynthetic pigmentsGrana – Stacks of thylakoids (resemble stacks of pancakes)Stroma – Solution surrounding the thylakoidsChlorophyll- light collecting pigment located on the thylakoid disks
7CHLOROPHYLL and PIGMENTS The most common and important photosynthetic pigments in plants and algae.Absorbs violet, blue, and red lights.Reflect and Transmit Green light – giving plants their GREEN color.Chlorophyll a – primary photosynthetic pigmentAccessory Pigments – Chlorophyll b and carotenoids
9LIGHT REACTIONS Initial reactions of photosynthesis Begins with absorption of light in chloroplasts (in the thylakoids) to create chemical energy (ATP and NADPH)adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide diphosphate (NADPH2).
10Light rxn.Water molecules are split, creating electrons, protons, and oxygen as a byproductanimation
12Chemiosmosis The synthesis of ATP Occurs when there is a concentration gradient of protons across the thylakoid membraneADP ATP
13CALVIN CYCLE Second set of reactions in photosynthesis Is not dependent on lightOccurs in the stroma(liquid area of the chloroplast) when ATP and NADPH are presentMakes stored energy (in the form of carbs) that the plant can use
14How is this done?Carbon fixation: carbon atoms are bonded (“fixed”) into organic compoundsaided by enzymesReactants: CO2 + ATP + NADPH + H+Products: O2 + C6H12O6
20Notebook quiz Write the equation for photosynthesis out in words? Where in the chloroplast do the light reactions occur?What are the products of the light reaction?What are the products of the Calvin Cycle?What is the primary photosynthetic pigment in plants?
21ALTERNATIVE PATHWAYS STOMATA – small pores in leaves of plants C4 Plants – close stomata during hot parts of the day (still able to produce carbohydrates)EX: corn, sugar cane, crabgrassCAM Plants – open stomata at night and close them during the day…producing organic compounds at nightEX: cactus, pineapples
22MAKING ENERGY animation CELLULAR RESPIRATIONMAKING ENERGYanimation
23CELLULAR RESPIRATION C6H12O6 + 6O2 6CO2+6H2O+ energy(ATP) The complex process in which cells make ATP by breaking down organic compoundsHeterotrophs – Organisms that obtain energy from eating autotrophs or other heterotrophs
24GLYCOLYSIS The beginning of cellular respiration Glucose is converted into 2 molecules of pyruvic acidProduces very little ATP and NADHglucosepyruvic acid
25GLYCOLYSIS PRODUCTION Glycolysis USES 2 ATP molecules to start the pathwayGlycolysis MAKES 4 ATP molecules at the end of glycolysisTherefore, glycolysis produces:Net total of 2 ATPNADH2 molecules of Pyruvic Acid
26With Oxygen…glycolysis is followed by AEROBIC RESPIRATION to produce more ATP Examples of aerobic exercise: long distance activitiesWithout Oxygen…glycolysis is followed by FERMENTATION (anaerobic respiration) producing no ATPExamples of anaerobic exercise: sprinting
27FERMENTATION Without Oxygen…Glycolysis goes to Anaerobic Respiration Does not produce ATPRecycles NAD+ from NADPH to keep glycolysis going2 most common fermentation pathways:LACTIC ACID FERMENTATIONETHYL ALCOHOL FERMENTATION
28LACTIC ACID FERMENTATION Converts pyruvic acid into lactic acidHelps produce some foodsex) yogurts and cheesesAlso occurs in your muscle cells during very strenuous exerciseex) sprintingAs lactic acid accumulates…it reduces the ability of the muscle cells to contract…resulting in fatigue, pain, and cramping
29ALCOHOLIC FERMENTATION Used by some plant cells and unicellular organismsConverts pyruvic acid into ethyl alcoholUsed in the wine and beer industries and in the making of breads
30Electron Transport Chain AEROBIC RESPIRATIONOccurs when Oxygen is present in the cellPyruvic acid is converted to CO2 and waterProduces large amounts of ATPTakes place in the mitochondria2 major stages:The Kreb’s CycleElectron Transport Chain
32THE KREB’S CYCLEOccurs in the mitochondrial MATRIX (space inside the inner membrane of the mitochondria)Biochemical pathway that breaks down acetyl CoA, and produces CO2, hydrogen atoms, and ATP1 Glucose molecule gives 2 cycles of the Kreb’s cycle and produces:6 NADH2 FADH22 ATP4 CO2
33ELECTRON TRANSPORT CHAIN Second stage of aerobic respiration…occurs along the many folds (cristae) of the mitochondria4 NADH from Glycolysis produce a total of ATP6 NADH from Kreb’s produce a total of 18 ATP2 FADH2 from Kreb’s produce a total of 4 ATPElectron Transport Chain Produces a TOTAL of 34 ATP
34THE ENTIRE PROCESS CAN PRODUCE A TOTAL OF 38 ATP CELLULAR RESPIRATIONTHE ENTIRE PROCESS CAN PRODUCE A TOTAL OF 38 ATP
36Why do leaves change color in the fall? How do annuals and perennials survive winter?Why do deciduous trees loose their leaves and evergreens do not loose their needles?Why do the leaves fall from the trees in autumn?How and why do the leaves separate from the tree?What is anthocyanin?Name other pigments that appear in leaves after the chlorophyll disappears.Where is the best place to see the color change? Why?
37Photosynthesis Comic Directions Create a minimum 6 slide comic strip summarizing the process of photosynthesis .Be sure to include the reactants and products of the light and dark reactions.
38Cellular Respiration Poster! Design a poster summarizing all important parts of the stages of aerobic and anaerobic cellular respiration.Show how all of the processes are relatedBe creativeBe prepared to show your poster to the rest of the class and explain its contents
39Notebook Quiz Distinguish between autotrophs and heterotrophs. What are the (3) products of glycolysis?After glycolysis, what determines the next step?What type of fermentation occurs in animal cells?What are the 2 steps of aerobic respiration?How many ATP are produced in cellular respiration?
40Notebook Quiz What is the primary photosynthetic pigment in plants? In photosynthesis, where do the light reactions occur? Where does the Calvin Cycle occur?What is the chemical energy produced in photosynthesis?What molecule made in photosynthesis is “burned” in cellular respiration?Distinguish between autotrophs and heterotrophs.What are the 3 products of glycolysis?After glycolysis, what determines the next step?