Cell Energy

Why do cells need energy? *ALL ORGANISMS NEED ENERGY To undergo mitosis To maintain homeostasis To make more energy Active Transport Nerve transmission Muscle Contraction Bioluminescence (glowing)

How do Cells Store Energy? ATP Adenosine Triphosphate Made of : 1 Adenine molecule 1 Ribose sugar molecule 3 Phosphate moleucles Energy is stored in the bonds between theses molecules!

ATP molecules are constantly burned! Why the need for ATP? Light energy is not absorbed in plants quickly enough without ATP In animals, energy is used very quickly ATP molecules are constantly burned! ADP- Adenosine diphosphate ATP ADP + phosphate Energy is released! AMP- Adenosine monophosphate ADP AMP + phosphate

How is ATP made? ATP A-P ≈P ≈P ADP A-P ≈P Nerve Conduction and active transport (uses ATP) Photosynthesis and Respiration (makes ATP) ADP A-P ≈P

Photosynthesis Photo= Light Syntheis= To make The process in which plants use solar energy to create energy (ATP) Plants use the CO2 (carbon dioxide) that animals breathe Plants make O2 (oxygen) and glucose

Photosynthesis happens in the chloroplast Chloro= green -Plast= plastid Contains chlorophyll which absorbs the sun’s energy Thylakoid: Membrane that absorbs the sun’s energy Grana: Stacks of thylakoids Stroma: Fluid found inside of the chloroplast

Equation for Photosynthesis LIGHT 6 CO2 + 6 H2O C6H12O6 + 6O2 Chlorophyll REACTANTS PRODUCTS Raw Materials: CO2 and H2O, which are both inorganic Product: Glucose

Light Dependant vs. Light Independent Light dependant: needs energy from the sun to act as a catalyst for reactions to happen Light independent: does not need energy from the sun, uses molecules made in the light dependant reactions to make energy Also called the Calvin Cycle

Process of Light Dependant Photosynthesis: Light energy is absorbed and changed to chemical energy Light energy is then transferred to the chlorophyll molecules in the thylakoid membrane Chlorophyll acts as a catalyst The energy level of the electrons rises due to light energy This creates enough energy for photosynthesis to begin Water splits into 2 H+ and O ADP is made into ATP Stores energy O2 is released Used for respiration

Process of Light Independent Photosynthesis (Calvin Cycle) ATP and NADPH (energy “helper” molecule) molecules are used- products of light dependant reaction A carbon molecule in a carbohydrate is changed, which makes glucose “Carbon Fixation” Glucose is a high energy molecule

Cell Respiration Chemical energy from glucose and other food molecules is released Is the process in which plants and animals release ATP

Cell respiration happens on the mitochondria The mitochondria is a double layered organelle Folds inside are called cristae (increase surface area so more ATP can be made)

Equation for cell respiration Respiratory C6H12O6 + 6O2 6CO2+6H20 + 38 ATP Enzymes REACTANTS PRODUCTS The equation of cell respiration is the opposite of photosynthesis!

Two stages of cell respiration Glycolysis: Anaerobic Happens in the cytoplasm of cell Produces two ATP molecules Kreb’s Cycle: Aerobic Electron Transport Chain (34 ATP) Happens in the mitochondria For every cycle of the Kreb’s Cycle, 1 ATP is made http://highered.mcgraw-hill.com/sites/9834092339/student_view0/chapter7/how_the_krebs_cycle_works.html

Fermentation: Happens after the Kreb’s Cycle if oxygen is not present IN PLANTS: Alcoholic fermentation End product is ethyl alcohol Used in brewing and baking (yeast) End product is glucose IN ANIMALS: Lactic Acid fermentation Accumulates in human muscle tissue. End product is muscle fatigue Used to make pickles, yogurt, buttermilk, sauerkraut

Cell Respiration ATP Totals Glycolysis 2 ATP Kreb’s Cycle 2 ATP Electron Transport 34 ATP Total 38 ATP