Cell Energy Photosynthesis and Respiration
Section 1 • Thermodynamics • Metabolism • Photosynthesis • cellular respiration • Adenosine Triphosphate
Energy objectives: 1. Explain that living things need energy to fight entropy, grow, develop, maintain homeostasis,and move etc. The 2nd Law of Thermodynamics states that all things move toward disorder (entropy) spontaneously! Livings things maintain order! This requires lots of energy! The ultimate source of this energy is…
Metabolism • Living things break down things, which often releases energy.: catabolism • Living things build up things, which often requires energy: anabolism • Together these processes are known as metabolism.
Photosynthesis captures this energy of the sun and transfers it to Form bonds in organic molecules like glucose. Be able to: Write the equation for photosynthesis: 6CO2 + 6H2O light C6H12O6 + 6O2
During photosynthesis: • energy produced by splitting water in the light dependent reactions is used to bond Carbon dioxide into glucose (sugar) in the light independent reactions
Energy is transferred from the bonds of glucose to… • The bonds of ATP
Explain that energy is stored in an ATP molecule in the phosphate to phosphate bonds and how it can be released when those bonds are broken producing ADP + P + energy.
This can be accomplished by Respiration • Which transfers the energy in the chemical bonds of organic molecules like glucose and stores it in the bonds of molecules like ATP where it is more easily released when needed by the cell for other chemical reactions. • Glucose + oxygen yields carbon dioxide + water plus ATP
Respiration Write the equation for respiration: C6H12O6 + 6O2 6CO2 + 6H2O
Respiration starts in the cytoplasm and finishes in the mitochondrion Know that when oxygen is present it is called aerobic respiration and is much more efficient at producing ATP and that when oxygen is not present it is called anaerobic when no oxygen is used and it is less efficient at producing ATP.
ATP is the molecule that stores energy for easy use within the cell. ATP is formed when a phosphate group is added to ADP. When ATP is broken down, ADP and phosphate are formed and energy is released.
Green organisms trap the energy in sun light and store it in the bonds of certain molecules for later use. They are called Autotrophs. Organisms that can not use sunlight directly obtain energy by consuming plants or other organisms that have consumed plants. They are called Heterotrophs!!! Photosynthesis is the process by which cells use light energy to make simple sugars.
Chlorophyll in the chloroplast of plant cells “traps” light energy needed for photosynthesis. • The light reactions of photosynthesis produce ATP and NADPH and result in the splitting of water molecules. • The reactions of the carbon cycle make carbohydrates using CO2 along with ATP and NADPH from the light reactions.
In cellular respiration, cells break down carbohydrates to release energy. • The first stage of cellular respiration, Glycolysis, takes place in the cytoplasm and does not require oxygen. • The citric acid cycle takes place in mitochondria and requires oxygen.
ATP 3 parts1. sugar: ribose2. nitrogen base: adenine3. 3 Phosphate groups
MAKING ATP: AMP + P = ADP ADP + P = ATP ATP = ADP + ENERGY • ATP SYNTHASE is the enzyme that attaches the third phosphate to the molecule. This enzyme is located in the thylakoid membrane and is like a rotary engine. The movement of H+ ions through it spins the enzyme, providing the energy to bond a P on to the ADP.
Autotroph or Heterotroph? • Do they “make” their own energy source?
Autotrophs/producers • Autotrophs, such as plants, use photosynthesis to convert light energy from the Sun into Chemical energy, which is stored in Carbohydrates and other Organic Compounds.
Heterotrophs • Both Autotrophs and Heterotrophs depend on these Organic Compounds for the energy to Power Cellular Activities
SC. 912.L.18.10 Connect the role of adenosine triphosphate (ATP) to energy transfers within the cell
What are the three parts of ATP? • Ribose, sugar, 2 phosphates • Sugar, 1 phosphate and a nitrogen base • Adenine, sugar and 3 phosphates • Adenine, deoxyribose and 3 phosphates.
What is the molecule that most often used as a source of energy for chemical reactions in the cell? • Glucose • ATP • ADP • NADPH • Starch
What is the original source of energy for all living things on earth? • Fossil fuels • Uranium • Sunlight • Wind • Hydroelectric
1. Why do living things need energy? • To make new cells. • To break down • To stay organized • All of these are ways to fight entropy and are correct.
What does the 2nd law of thermodynamics say about entropy? • It takes energy to maintain entropy • All things move toward entropy spontaneously. • Living things have lots of entropy.
What kind of organisms can use sunlight to make food for themselves? • Heterotrophs • Autotrophs • Consumers • Decomposers
What are the catabolic and anabolic reactions of the cell together known as? • Catabolism • Anabolism • Metabolism
What is required to fight the entropy that the 2nd law says will spontaneously occur? • ATP • Catabolism • Anabolism • Photosynthesis • All of these might work
7. What does ATP become when it loses a phosphate group? _______ 8. Where in the ATP molecule is the energy stored? _______________________________________________________ 9. How does ATP release energy? _____________________________________________________________________ 10. Write the equation that shows the release of energy from ATP. ___________________________________________ ________________________________________ 11. What is the main role that ATP plays within a cell? ____________________________________________________________________________________________________ 12. Why are the processes of photosynthesis and cellular respiration considered a cycle? ___________________________ _________________________________________________________________________________________________
7. What does ATP become when it loses a phosphate group? ADP 8. Where in the ATP molecule is the energy stored? In the chemical bonds 9. How does ATP release energy? Energy is released when the bonds between the phosphates are broken. 10. Write the equation that shows the release of energy from ATP. ATP ADP + P 11. What is the main role that ATP plays within a cell? When coupled with other chemical reactions, it supplies energy for activation for many chemical reactions. 12. Why are the processes of photosynthesis and cellular respiration considered a cycle? The products of one are the reactants of the other, they supply each other with what is needed!
Section 2 Photosynthesis • Vocabulary: • 1. Thylakoid • 2. Granum • 3. Stroma • 4. Pigment • 5. NADP • 6. Calvin cycle • 7. Light Reactions
2. Granum • 1. Thylakoid 3. Stroma 4. Pigment
7. Light Reactions6. Calvin cycle • 5. NADP
Photosynthesis • the process by which plants make sugar from sunlight, water, and carbon dioxide):
Sunlight shines through the top of the leaf and reaches the next layer of cells. • The light energy is trapped by the chlorophyll in the chloroplasts. • In the chloroplasts, a process that uses water changes the light energy into a kind of chemical energy. This chemical energy is stored in the chloroplasts. The electrons in chlorophyll are excited and travel down electron transport chains!
Air enters the leaf through the stomata and moves into tiny spaces around the food-making cells in the leaf. • Carbon dioxide from the air passes through the cell walls and membranes of the cells. • Carbon dioxide enters the chloroplasts where the previously stored chemical energy converts the carbon dioxide into sugar.
Phloem tubes in the plant carry sugar from the leaf cells to other parts of the plant, such as roots, stems, and fruits. • Cells in these parts of the tree store some of the sugar