Cellular Respiration

Both plant and animal cells carry out the final stages of cellular respiration in the mitochondria. Outer membrane Intermembrane space Mitochondrion Inner membrane Photo Credits: left: ©Bob Gurr/DRK Photo; middle bottom: ©John Durham/Science Photo Library/Photo Researchers, Inc. ; middle top: ©Ron Boardman/Stone; right: ©Keith Porter/Photo Researchers, Inc. Matrix Plant Cells 2

Cells Using Biochemical Energy All cells need to make ATP energy Prokaryotes and Eukaryotes Cells Use ATP For: Movement Photosynthesis Protein Synthesis Cellular respiration All other cellular reactions Amoeba 3

Releasing Energy From ATP ATP provides all of the energy for cell activities The high energy phosphate bonds can be BROKEN to release energy ATP is constantly being used and remade by cells 4

ATP consists of: adenine ribose (a 5-carbon sugar) 3 phosphate groups ATP is used by all types of cells as their basic energy source. ATP 5

Adenosine Triphosphate (ATP) Adenosine Diphosphate (ADP) + Phosphate Storing Energy ADP has two phosphate groups instead of three, so adding a phosphate group to ADP stores energy in ATP (3 phosphate groups) ATP ADP Energy + Energy Adenosine Triphosphate (ATP) Adenosine Diphosphate (ADP) + Phosphate Partially charged battery Fully charged battery 6

Releasing Energy Energy stored in ATP is released by breaking the chemical bond between the second and third phosphates. 2 Phosphate groups P ADP 7

Releasing Energy From ATP Adding A Phosphate Group To ADP stores Energy in ATP Removing A Phosphate Group From ATP Releases Energy & forms ADP Loose Gain 8

Cellular Respiration C6H12O6 + 6O2  6CO2 + 6H2O + energy A process that uses energy extracted from (glucose) to produce energy (ATP) and water (H2O). C6H12O6 + 6O2  6CO2 + 6H2O + energy glucose ATP Compare to equation for photosynthesis 9

What is created?? 38 ATP!!!!! A compound Used To Store Energy In Living Organisms 10

What are the two types of cellular respiration? There are two types of cellular respiration Anaerobic (without oxygen) pathways Aerobic (with oxygen) pathways Both pathways begin with glycolysis: break down of glucose. Takes place in the cytoplasm Generate 2 ATP

Mitochondria Organelle where Aerobic cellular respiration takes place. Inner membrane space Matrix Cristae Outer membrane Inner membrane 12

Aerobic Cellular Respiration

AEROBIC VS ANAEROBIC respiration? What happens during AEROBIC VS ANAEROBIC respiration? AEROBIC RESPIRATION: Occurs in the PRESENCE of oxygen. 38 ATP can be produced ANAEROBIC RESPIRATION: Occurs in the ABSENCE of oxygen.. 2 ATP produced 2 main types of fermentation: Lactic Acid Fermentation Alcoholic Fermentation

Fermentation Occurs when O2 NOT present (anaerobic) Called Lactic Acid fermentation in muscle cells (makes muscles tired) Produced in your muscles during rapid exercise Occurs when O2 supply is short Called Alcoholic fermentation in yeast (produces ethanol) 15

Cellular Respiration C6H12O6 + 6O2 6CO2 + 6H2O + Energy (ATP)

What are the most important chemical reactions on Earth? Photosynthesis is the process by which some organisms capture the energy of sunlight and convert it to chemical energy that is stored as food 6CO2 + 6H2O  C6H12O6 + 6O2 Cellular respiration is the process by which all organisms obtain energy from the chemical bonds in food molecules. 6O2 + C6H12O6  6CO2 + 6H2O + Energy 18

How are photosynthesis and cellular respiration related? The key cellular process for energy production is photosynthesis. 6CO2 + 6H2O + Light → C6H12O6 + 6O2 Takes place in chloroplasts Energy is released during cellular respiration by breaking down glucose. C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP Takes place in mitochondria The energy flow in photosynthesis and cellular respiration takes place in opposite directions. Photosynthesis captures energy. Cellular respiration releases energy.

Photosynthesis vs. Cellular Respiration Converts energy to food Performed by autotrophs Takes place in the Chloroplast Reactants: CO2, H2O, and Light Energy Products: O2 and C6H12O6 (aka- glucose… FOOD!) Converts food into energy Performed by heterotrophs and plants Takes place in the mitochondria Reactants: Glucose (C6H12O6) and O2 Products: CO2 , H2O, and ATP (energy!)

Review Questions

The numbered boxes in the diagram represent which of the following?  1 - water; 2 - nitrogen 1 - nitrogen; 2 - oxygen 1 - oxygen; 2 - carbon dioxide 1 - carbon dioxide; 2 - water

Copyright Pearson Prentice Hall Glycolysis occurs in the mitochondria. cytoplasm. nucleus. chloroplasts. Copyright Pearson Prentice Hall 24

Copyright Pearson Prentice Hall Fermentation releases energy from food molecules in the absence of oxygen. glucose. NADH. alcohol. Copyright Pearson Prentice Hall 25

Copyright Pearson Prentice Hall How is energy released from ATP? A phosphate is added. An adenine is added. A phosphate is removed. A ribose is removed. Copyright Pearson Prentice Hall 26

Copyright Pearson Prentice Hall How is it possible for most cells to function with only a small amount of ATP? Cells do not require ATP for energy. ATP can be quickly regenerated from ADP and P. Cells use very small amounts of energy. ATP stores large amounts of energy. Copyright Pearson Prentice Hall 27

Copyright Pearson Prentice Hall Compared to the energy stored in a molecule of glucose, ATP stores much more energy. much less energy. about the same amount of energy. more energy sometimes and less at others. Copyright Pearson Prentice Hall 28

What function does ATP carry out in living things? aids in protein folding and coiling used to capture and transfer energy identifies DNA start sequences for transcription helps maintain the fluidity of cell membranes

How are cellular respiration and photosynthesis related, in terms of energy? The energy captured in photosynthesis is used to power cellular respiration. The energy transformed in cellular respiration is used to power photosynthesis. Photosynthesis and respiration perform the same task in terms of energy transformation. Energy is not involved in either photosynthesis or cellular respiration.