Chapter 6 Photosynthesis & Cellular Respiration

Energy and Living Things

Flow of Energy SUN Producers Primary Consumer Secondary Consumers Decomposers (recycled nutrients) Solar Energy

Autotrophs Autotrophs are organisms that make their own food using sunlight –Plants and some bacteria are autotrophs Photosynthesis- the process of converting sunlight(solar energy) into food(glucose) Chemical Equation: CO 2 + H 2 O  C 6 H 12 O 6 + O 2 Carbon DioxideWaterGlucoseOxygen

Heterotrophs Heterotrophs are organisms that can not make their own food, so they eat other organisms for food –Animals, fungi, and protists are heterotrophs Cellular Respiration- the metabolic process of breaking down food to release energy - cellular respiration converts food energy into ATP to power cells Chemical Equation: C 6 H 12 O 6 + O 2  CO 2 + H 2 O

ATP ATP = Adenosine Triphosphate –ATP is the primary source of energy in cells ATP can be converted to ADP by removing a phosphate –ADP = adenosine diphosphate ADENOSINE TRIPHOSPHATE

ATP  ADP Converting ATP to ADP releases energy!!! ATP  ADP + P + Energy

ATP Molecular Diagram

Endergonic Reactions Endergonic Reactions require or use energy during the chemical reaction Ex: PhotosynthesisReaction: Carbon Dioxide + Water + Light Energy  Glucose + Oxygen Cold Pack – absorbs energy

Exergonic Reactions Exergonic Reactions release or give off energy during the chemical reaction Ex: Cellular Respiration: Glucose + Oxygen  Carbon Dioxide + Water + Energy Heat Pack- releases energy Combustion Reaction- releases heat

Photosynthesis Photosynthesis is the process of converting sunlight into food(glucose) using chloroplasts Stage 1: Energy is Captured from Sunlight Stage 2: Light Energy is Converted to Chemical Energy(ATP) using Water Stage 3: CO 2 and ATP combine to produce Glucose(C 6 H 12 O 6 ) for the plant

Photosynthesis Equation 6 CO H 2 O > C 6 H 12 O O 2 Carbon Dioxide WaterGlucoseOxygen Sunlight

Chloroplasts Chloroplasts are organelles that allow plants to perform photosynthesis Chlorophyll: a green pigment in chloroplasts that traps sunlight for photosynthesis * plants have 2 types of chlorophyll, type a & b Carotenoids: a yellow/orange pigment that absorbs different wavelengths of light than chlorophyll * carotenoids are more visible in the fall

Color Absorption

Structure of Chloroplasts

Chemical Reactions in Chloroplasts Light H2OH2OH2OH2O O2O2 CO 2 Glucose Light Reactions Calvin Cycle ATP + +

Light Reactions Light reactions occur in the thylakoids of the chloroplast Light reactions use sunlight & water(H 2 O) to make oxygen(O 2 ) and ATP Light reactions only occur when the plant is exposed to sunlight

Calvin Cycle The Calvin Cycle occurs in the stroma of the chloroplast The Calvin Cycle uses ATP and carbon dioxide(CO 2 ) to produce Glucose and ATP

Steps of the Calvin Cycle 1)CO 2 is combined with a 5-carbon molecule by an enzyme forming a 6-carbon molecule 2)The 6-carbon molecule is split into two 3-carbon molecules 3)One of the 3-carbon molecules is used to make glucose 4)The other 3-carbon molecule is used to replace the 5-carbon molecule used in step 1

Diagram of the Calvin Cycle Step 1: CO carbon molecule 6-carbon molecule Step 2: 3-carbon molecules Step 4: Step 3: Glucose O 2 released

Calvin Cycle

Cellular Respiration Cellular Respiration is the process of breaking down food(glucose) to release energy(ATP) * ALL LIVING THINGS PERFORM CELLULAR RESPIRATION - plants, animals, bacteria, fungi, etc…

Steps of Cellular Respiration Stage 1: Glycolysis –Glucose is converted to pyruvate Stage 2: Aerobic or Anaerobic Respiration –If O 2 is present, pyruvate & O 2 produce CO 2 (carbon dioxide) and H 2 O(water) AEROBIC RESPIRATION –If O 2 is not present, pyruvate breaks down into CO 2 (carbon dioxide) and lactic acid or ethanol ANAEROBIC RESPIRATION

Glycolysis Glycolysis is the process of breaking down glucose to make pyruvate Glucose6-carbon compound 3-carbon compounds Pyruvate KEY = carbon = phosphate

Aerobic Respiration Aerobic Respiration uses O 2 Chemical Equation: Pyruvate + O 2  CO 2 + H 2 O + 36 ATP

Anaerobic Respiration Anaerobic respiration does not use O 2 Alcoholic Fermentation: Pyruvate  CO 2 + ethanol + 2 ATP Lactic Acid Fermentation: Pyruvate  CO 2 + lactic acid + 2 ATP

END OF CHAPTER 6 NOTES!!!