Chapter 8 Cellular Energy Section 1: How Organisms Obtain Energy Section 2: Photosynthesis Section 3: Cellular Respiration

Transformation of Energy Chapter 8 Cellular Energy 8.1 How Organisms Obtain Energy Transformation of Energy Energy is the ability to do work. Thermodynamics is the study of the flow and transformation of energy in the universe.

Laws of Thermodynamics Chapter 8 Cellular Energy 8.1 How Organisms Obtain Energy Laws of Thermodynamics First law—energy can be converted from one form to another, but it cannot be created nor destroyed. Second law—energy cannot be converted without the loss of usable energy.

Autotrophs and Heterotrophs Chapter 8 Cellular Energy 8.1 How Organisms Obtain Energy Autotrophs and Heterotrophs Autotrophs are organisms that make their own food. Heterotrophs are organisms that need to ingest food to obtain energy.

All of the chemical reactions in a cell Chapter 8 Cellular Energy 8.1 How Organisms Obtain Energy Metabolism All of the chemical reactions in a cell Photosynthesis—light energy from the Sun is converted to chemical energy for use by the cell Cellular respiration—organic molecules are broken down to release energy for use by the cell

ATP: The Unit of Cellular Energy Chapter 8 Cellular Energy 8.1 How Organisms Obtain Energy ATP: The Unit of Cellular Energy ATP releases energy when the bond between the second and third phosphate groups is broken, forming a molecule called adenosine diphosphate (ADP) and a free phosphate group.

Overview of Photosynthesis Chapter 8 Cellular Energy 8.2 Photosynthesis Overview of Photosynthesis Photosynthesis occurs in two phases. Light-dependent reactions Light-independent reactions

Phase One: Light Reactions Chapter 8 Cellular Energy 8.2 Photosynthesis Phase One: Light Reactions The absorption of light is the first step in photosynthesis. Chloroplasts capture light energy.

Chapter 8 Cellular Energy 8.2 Photosynthesis Electron Transport Light energy excites electrons in photosystem II and also causes a water molecule to split, releasing an electron into the electron transport system, H+ into the thylakoid space, and O2 as a waste product.

Chapter 8 Cellular Energy 8.2 Photosynthesis The excited electrons move from photosystem II to an electron-acceptor molecule in the thylakoid membrane. The electron-acceptor molecule transfers the electrons along a series of electron-carriers to photosystem I.

Photosystem I transfers the electrons to a protein called ferrodoxin. Chapter 8 Cellular Energy 8.2 Photosynthesis Photosystem I transfers the electrons to a protein called ferrodoxin. Ferrodoxin transfers the electrons to the electron carrier NADP+, forming the energy-storing molecule NADPH. Visualizing Electron Transport

Phase Two: The Calvin Cycle Chapter 8 Cellular Energy 8.2 Photosynthesis Phase Two: The Calvin Cycle In the second phase of photosynthesis, called the Calvin cycle, energy is stored in organic molecules such as glucose.

Chapter 8 Cellular Energy 8.2 Photosynthesis Six CO2 molecules combine with six 5-carbon compounds to form twelve 3-carbon molecules called 3-PGA. The chemical energy stored in ATP and NADPH is transferred to the 3-PGA molecules to form high-energy molecules called G3P.

Chapter 8 Cellular Energy 8.2 Photosynthesis Two G3P molecules leave the cycle to be used for the production of glucose and other organic compounds. An enzyme called rubisco converts the remaining ten G3P molecules into 5-carbon molecules called RuBP. These molecules combine with new carbon dioxide molecules to continue the cycle.

Alternative Pathways C4 plants CAM plants 8.2 Photosynthesis Chapter 8 Cellular Energy 8.2 Photosynthesis Alternative Pathways C4 plants CAM plants

Overview of Cellular Respiration Chapter 8 Cellular Energy 8.3 Cellular Respiration Overview of Cellular Respiration Organisms obtain energy in a process called cellular respiration. The equation for cellular respiration is the opposite of the equation for photosynthesis.

Cellular respiration occurs in two main parts. Chapter 8 Cellular Energy 8.3 Cellular Respiration Cellular respiration occurs in two main parts. Glycolysis Aerobic respiration

Chapter 8 Cellular Energy 8.3 Cellular Respiration Glycolysis Glucose is broken down in the cytoplasm through the process of glycolysis. Two molecules of ATP and two molecules of NADH are formed for each molecule of glucose that is broken down.

Glycolysis has a net result of two ATP and two pyruvate. Chapter 8 Cellular Energy 8.3 Cellular Respiration Krebs Cycle Glycolysis has a net result of two ATP and two pyruvate. Most of the energy from the glucose is still contained in the pyruvate. The series of reactions in which pyruvate is broken down into carbon dioxide is called the Krebs cycle.

Chapter 8 Cellular Energy 8.3 Cellular Respiration The net yield from the Krebs cycle is six CO2 molecules, two ATP, eight NADH, and two FADH2.

Final step in the breakdown of glucose Chapter 8 Cellular Energy 8.3 Cellular Respiration Electron Transport Final step in the breakdown of glucose Point at which ATP is produced Produces 24 ATP

Anaerobic Respiration Chapter 8 Cellular Energy 8.3 Cellular Respiration Anaerobic Respiration The anaerobic pathway that follows glycolysis Two main types Lactic acid fermentation Alcohol fermentation Cellular Respiration

Chapter Resource Menu Chapter Diagnostic Questions Cellular Energy Chapter Resource Menu Chapter Diagnostic Questions Formative Test Questions Chapter Assessment Questions Standardized Test Practice biologygmh.com Glencoe Biology Transparencies Image Bank Vocabulary Animation Click on a hyperlink to view the corresponding lesson.

Which statement describes the law of conservation of energy? Chapter 8 Cellular Energy Chapter Diagnostic Questions Which statement describes the law of conservation of energy? Energy cannot be converted or destroyed. Energy can be converted and destroyed. Energy can be converted but not destroyed. Energy can be destroyed but not converted.

In which metabolic process are molecules Chapter 8 Cellular Energy Chapter Diagnostic Questions In which metabolic process are molecules broken down to produce carbon dioxide and water? photosynthesis cellular respiration homeostasis fermentation

At the end of the Calvin cycle, where is energy stored? Chapter 8 Cellular Energy Chapter Diagnostic Questions At the end of the Calvin cycle, where is energy stored? NADPH ATP chloroplast glucose

Which law of thermodynamics explains Chapter 8 Cellular Energy 8.1 Formative Questions Which law of thermodynamics explains why the ladybug receives the least amount of usable energy?

the first law of thermodynamics the second law of thermodynamics Chapter 8 Cellular Energy 8.1 Formative Questions the first law of thermodynamics the second law of thermodynamics

All of the energy from the food you eat comes from the sun. Chapter 8 Cellular Energy 8.1 Formative Questions True or False All of the energy from the food you eat comes from the sun.

Why is cellular respiration a catabolic pathway? Chapter 8 Cellular Energy 8.1 Formative Questions Why is cellular respiration a catabolic pathway? Energy is used to form glucose and oxygen. Energy is converted from water to carbon dioxide. Energy that is lost is converted to thermal energy. Energy is released by the breakdown of molecules.

Why is adenosine triphosphate (ATP) such an Chapter 8 Cellular Energy 8.1 Formative Questions Why is adenosine triphosphate (ATP) such an important biological molecule? It captures light energy from the sun. It is produced in anabolic pathways. It stores and releases chemical energy. It converts mechanical energy to thermal energy.

Where in the plant cell does photosynthesis take place? Chapter 8 Cellular Energy 8.2 Formative Questions Where in the plant cell does photosynthesis take place? chloroplasts Golgi apparatus mitochondria vacuoles

Which range of wavelengths is reflected by chlorophylls a and b? Chapter 8 Cellular Energy 8.2 Formative Questions Which range of wavelengths is reflected by chlorophylls a and b? 400-500 nm 500-600 nm 600-700 nm

Which mechanism of photosynthesis uses Chapter 8 Cellular Energy 8.2 Formative Questions Which mechanism of photosynthesis uses the movement of hydrogen ions (H+) across a concentration gradient to synthesize ATP? absorption chemiosmosis electron transport C2 pathway

How are the C4 pathway and the CAM pathway Chapter 8 Cellular Energy 8.2 Formative Questions How are the C4 pathway and the CAM pathway an adaptive strategy for some plants? They accelerate photosynthesis. They release more oxygen. They help the plant conserve water. They reduce the requirement for ATP.

What is the overall purpose of cellular respiration? Chapter 8 Cellular Energy 8.3 Formative Questions What is the overall purpose of cellular respiration? to make ATP to process H2O to store glucose to deliver oxygen

Which represents the general sequence of cellular respiration? Chapter 8 Cellular Energy 8.3 Formative Questions Which represents the general sequence of cellular respiration? TCA cycle chemiosmosis glycolysis glycolysis Krebs cycle electron transport electron absorption catalysis phosphorylation fermentation aerobic pathway anaerobic pathway

Which stage of cellular respiration is the anaerobic process? Chapter 8 Cellular Energy 8.3 Formative Questions Which stage of cellular respiration is the anaerobic process? glycolysis Krebs cycle electron transport

Which molecule generated by the Krebs cycle is a waste product? Chapter 8 Cellular Energy 8.3 Formative Questions Which molecule generated by the Krebs cycle is a waste product? CoA CO2 FADH2 NADH

Look at the following figure. Which part of the Chapter 8 Cellular Energy Chapter Assessment Questions Look at the following figure. Which part of the chloroplast is a sac-like membrane arranged in stacks? grana stroma thylakoids Golgi apparatus

pyruvate is broken down into what compound? Chapter 8 Cellular Energy Chapter Assessment Questions During the Krebs cycle, pyruvate is broken down into what compound? H2O O2 CO CO2

Look at the following figure. Which molecule is Chapter 8 Cellular Energy Chapter Assessment Questions Look at the following figure. Which molecule is released when ATP becomes ADP? phosphate group water molecule ribose sugar energy cells

A B Which metabolic process is photosynthesis? Chapter 8 Cellular Energy Standardized Test Practice Which metabolic process is photosynthesis? A B

At the beginning of photosynthesis, which Chapter 8 Cellular Energy Standardized Test Practice At the beginning of photosynthesis, which molecule is split to produce oxygen (O2) as a waste product? CO2 H2O C6H12O6 3-PGA

Which molecule helps provide the energy that drives this cycle? Chapter 8 Cellular Energy Standardized Test Practice Which molecule helps provide the energy that drives this cycle? 3-PGA CO2 NADPH rubisco

Which product of the Calvin cycle is used for Chapter 8 Cellular Energy Standardized Test Practice Which product of the Calvin cycle is used for the production of glucose and other organic compounds? ADP CO2 G3P NADP+

What is the final step of cellular respiration? Chapter 8 Cellular Energy Standardized Test Practice What is the final step of cellular respiration? O2 and H+ form H2O. Electrons and H2O generate ATP. C6H12O6 is broken down into CO2. NADH and FADH2 gain electrons.

What prevents pyruvate from entering the Krebs Chapter 8 Cellular Energy Standardized Test Practice What prevents pyruvate from entering the Krebs cycle and instead results in this pathway? a buildup of CO2 a lack of oxygen an excess of glucose an increased demand for ATP

Which is not a process that occurs in both Chapter 8 Cellular Energy Standardized Test Practice Which is not a process that occurs in both cellular respiration and glycolysis? chemiosmosis electron transport glycolysis production of G3P

Glencoe Biology Transparencies Chapter 8 Cellular Energy Glencoe Biology Transparencies

Chapter 8 Cellular Energy Image Bank

Section 1 Vocabulary energy thermodynamics metabolism Photosynthesis Chapter 8 Cellular Energy Vocabulary Section 1 energy thermodynamics metabolism Photosynthesis cellular respiration adenosine triphosphate (ATP)

Section 2 Vocabulary thylakoid granum stroma pigment NADP+ Chapter 8 Cellular Energy Vocabulary Section 2 thylakoid granum stroma pigment NADP+ Calvin cycle rubisco

Section 3 Vocabulary anaerobic process aerobic respiration Chapter 8 Cellular Energy Vocabulary Section 3 anaerobic process aerobic respiration aerobic process glycolysis Krebs cycle fermentation

Visualizing Electron Transport Chapter 8 Cellular Energy Animation Visualizing Electron Transport