Chapter 8 Photosynthesis

8-1 Energy and Life I. Autotrophs -make food using sunlight II. Heterotrophs - obtains energy from food they consume III. Energy is the “currency” of the cell A. ATP 1. Adenosine Triphosphate 2. Chemical compound cells use to store energy 3. PARTS: a. Adenine b. 3 phosphate groups c. Ribose (5 carbon sugar)

8-1 Continued B. ADP 1. Adenosine Diphosphate 2. Has 2 phosphate groups 3. Chemical compound that can be converted to ATP to store energy 4. HOW? a. Bond 1 more phosphate group 5. Analogy: Half charged battery b. Energy is in the bond between phosphate groups 4. Analogy  Fully charged battery

C. Releasing Energy 1. Break bond of second and third phosphate group and energy is released 2. ATP  ADP + P + Energy 3. ATP is the preferred energy source to power the cell activities 2 Phosphate groups ADP

D. ATP and Glucose 1. Glucose stores 90X more energy than 1 ATP molecule 2. Cells use ATP for quick energy not long term energy 3. Cells only store enough ATP for a few seconds of activity

8-2 Photosynthesis A. Process in which chloroplast convert light energy from CO 2 and H 2 O into O 2 and high energy carbohydrates (glucose) B. Photosynthesis Equation light 6CO 2 +6H 2 O  C 6 H 12 O 6 + 6O 2 carbon dioxide +water  glucose + oxygen IV. Photosynthesis

C. Light and Pigments 1. Chlorophyll a. green pigment in chloroplast that absorbs wavelengths of light b. 2 types: chlorophyll a and chlorophyll b 1. Absorb most wavelengths of light except green (why plants are green) c. In the fall, trees reabsorb chlorophyll and the other pigments are visible

8-3 Reactions of Photosynthesis V. Takes place inside the Chloroplast A. Thylakoids = saclike membranes that contain chlorophyll to capture light 1. granum = stacks of thylakiods B. Stroma = fluid filled space around thylakoids C. Two types of reactions 1. Light Dependent 2. Light Independent / Calvin Cycle / Dark Reaction Chloroplast Single thylakoid Granum Stroma

Light PHOTOSYNTHESIS CO 2 Calvin cycle O2O2 Sugars Light- dependent reactions NADP + ADP + P H 2 O p208

VI. Electron Carriers = Energy Carriers A. NADP+ = transport electrons (aka: Taxi) B. H+ = high energy electrons (aka: passengers) C. NADP+ picks up H+ and brings them elsewhere and drops them off D. NADPH drops off H+ for electron transfer at proteins that starts chemical reactions

VII. Light Dependent Reaction A. Requires light to take place E. Lost electrons are replaced by Hydrolysis (aka photolysis (splitting of water) D. Light strikes thylakoid; electrons excited; go to the ETC form NADPH and ATP, respectively. C. Uses light to split water for H; releases O 2 gas and makes high energy electrons & ATP B. Takes place in thylakoids

VIII. Calvin Cycle/Light Independent/ Dark Reactions A. Does not need light to take place D. Six turns of the Calvin Cycle makes 1 glucose molecule C. Powered by NADPH and ATP and uses 6CO 2 molecules to produce high energy sugar (glucose) B. Takes place in stroma

IX. Factors Affecting Photosynthesis A.Water shortage 1. slow/stop photosynthesis C. Light Intensity 1. increase light = speeds up photosynthesis 2. decrease light = slows down photosynthesis B. Temperature 1. enzymes cause photosynthesis to speed up 2. too hot = slow/ stop photosynthesis.

Chapter 9 Cellular Respiration

9-1 Chemical Pathways I. Cellular Respiration: A. Process by which mitochondria breaks down glucose to make ATP B. Cellular Respiration Equation: 6O 2 + C 6 H 12 O 6  6CO 2 + 6H 2 O Oxygen + Glucose  Carbon Dioxide + Water

Glycolysis Cytoplasm Glucose Electrons carried in NADH Pyruvic Acid Mitochondria Electrons carried in NADH and FADH 2 p222

2 ATP 2 ADP 4 ADP 4 ATP 2 Pyruvic acid d. Pyruvic Acid moves into the mitochondria 1) Produces 4 ATP but uses 2 ATP’s to start glycolysis c. Breaks down glucose into 2 molecules of pyruvic acid and produces 2 net ATP molecules b. Occurs in Cytoplasm 1. Glycolysis: a. anaerobic process =NO Oxygen is required C. Three Stages:

2. Krebs Cycle (aka. Citric Acid Cycle) a. Aerobic Respiration = Requires Oxygen b. Produces 2 ATP c. Releases CO 2, NADH, and FADH 2 d. NAD+ and FAD are “taxis”, take electrons to the ETC 3. Electron Transport Chain b. Oxygen is the Final Electron Acceptor c. Produces 32 ATP molecules a. Aerobic Respiration = Requires Oxygen

D. ATP Produced: 1. from Glycolysis 4 (2 are used to start therefore only 2 net) 2. from Krebs Cycle 2 3. from ETC Total of ATP molecules or net ATP 38 36

II. In the absence of Oxygen: Fermentation A. Anaerobic Respiration: (does NOT require O 2 ) 1. Follows glycolysis= 2ATP 2. TWO TYPES: a. Lactic Acid Fermentation 1) In animals 3) Lactic acid build up in muscles results in muscle fatigue 2) Pyruvic Acid used NADH to make 2 molecules of Lactic Acid pyruvic acid + NADH → lactic acid + NAD + b. Alcoholic Fermentation: 1) Used by yeast cells pyruvic acid + NADH → alcohol + CO 2 + NAD +

III. Comparing Photosynthesis and Cellular Respiration A. Photosynthesis and cellular respiration take place in opposite directions. Photosynthesis Cellular Respiration

B. Photosynthesisvs.Respiration 1. Food Made1. Food break down 2. Carbon Dioxide In2. Carbon Dioxide Out 3. Oxygen Out 3. Oxygen In 4. Makes Glucose 4. Breaks down Glucose 5. Happens in Light 5. Day and Night 6. Only with chlorophyll 6. All living cells 7. Takes place in Chloroplast7. Takes place in mitochondria

8-1 Organisms that make their own food are called A. autotrophs. B. heterotrophs. C. decomposers. D. consumers.

8-1 Most autotrophs obtain their energy from A. chemicals in the environment. B. sunlight. C. carbon dioxide in the air. D. other producers.

8-1 How is energy released from ATP? A. A phosphate is added. B. An adenine is added. C. A phosphate is removed. D. A ribose is removed.

8-1 How is it possible for most cells to function with only a small amount of ATP? A. Cells do not require ATP for energy. B. ATP can be quickly regenerated from ADP and P. C. Cells use very small amounts of energy. D. ATP stores large amounts of energy.

8-1 Compared to the energy stored in a molecule of glucose, ATP stores A. much more energy. B. much less energy. C. about the same amount of energy. D. more energy sometimes and less at others.

8-2 The raw materials required for plants to carry out photosynthesis are A. carbon dioxide and oxygen. B. oxygen and sugars. C. carbon dioxide and water. D. oxygen and water.

8-2 The principal pigment in plants is A. chloroplast. B. chlorophyll. C. carotene. D. carbohydrate.

8-2 The colors of light that are absorbed by chlorophylls are A. green and yellow. B. green, blue, and violet. C. blue, violet, and red. D. red and yellow.

8-3 In plants, photosynthesis takes place inside the a. thylakoids. b. chloroplasts. c. photosystems. d. chlorophyll.

8-3 Energy to make ATP in the chloroplast comes most directly from a. hydrogen ions flowing through an enzyme in the thylakoid membrane. b. transfer of a phosphate from ADP. c. electrons moving through the electron transport chain. d. electrons transferred directly from NADPH.

8-3 NADPH is produced in light-dependent reactions and carries energy in the form of a. ATP. b. high-energy electrons. c. low-energy electrons. d. ADP

8-3 What is another name for the Calvin cycle? a. light-dependent reactions b. light-independent reactions c. electron transport chain d. photosynthesis

8-3 Which of the following factors does NOT directly affect photosynthesis? a. wind b. water supply c. temperature d. light intensity

9-1 The raw materials required for cellular respiration are a. carbon dioxide and oxygen. b. glucose and water. c. glucose and oxygen. d. carbon dioxide and water.

9-1 Glycolysis occurs in the a. mitochondria. b. cytoplasm. c. nucleus. d. chloroplasts.

9-1 The net gain of ATP molecules after glycolysis is a. 3 ATP molecules. b. 2 ATP molecules. c. 3 pyruvic acid molecules. d. 4 pyruvic acid molecules

9-1 Fermentation releases energy from food molecules in the absence of a. oxygen. b. glucose. c. NADH. d. alcohol.

9-1 The first step in fermentation is always a. lactic acid production. b. the Krebs cycle. c. glycolysis. d. alcohol production.

9-2 The Krebs cycle breaks pyruvic acid down into a. oxygen. b. NADH. c. carbon dioxide. d. alcohol.

9-2 What role does the Krebs cycle play in the cell? a. It breaks down glucose and releases its stored energy. b. It releases energy from molecules formed during glycolysis. c. It combines carbon dioxide and water into high-energy molecules. d. It breaks down ATP and NADH, releasing stored energy.

9-2 In eukaryotes, the electron transport chain is located in the a. cell membrane. b. inner mitochondrial membrane. c. cytoplasm. d. outer mitochondrial membrane.

9-2 To generate energy over long periods, the body must use a. stored ATP. b. lactic acid fermentation. c. cellular respiration. d. glycolysis.

9-2 Which statement correctly describes photosynthesis and cellular respiration? a. Photosynthesis releases energy, while cellular respiration stores energy. b. Photosynthesis and cellular respiration use the same raw materials. c. Cellular respiration releases energy, while photosynthesis stores energy. d. Cellular respiration and photosynthesis produce the same products.