occurs in... 2 types Definition Equation? Reactants Products Extra Bonus Marks – Interestingly.....
Define cellular respiration Identify the energy source in cells and within a molecule of ATP Understand the link of ATP between catabolic and anabolic reactions Explain the process of phosphrylation Potential for LO3
Cellular Respiration Definition – Biochemical process by which energy- rich substrate molecules (foodstuff) are progressively broken down in enzymatic pathways to form adenosine triphosphate (ATP, high energy compound) Foodstuff is usually glucose. Glucose is broken down in a series of enzyme controlled steps. Hydrogen and high energy electrons are removed by dehydrogenase enzymes and used to yield ATP.
What is ATP? Adenosine Triphosphate is a molecule composed of: 1 x Adenosine (adenosine) 3 x inorganic phosphate (Pi) Pi Adenosine Bonds contain energy 3 Inorganic Phosphate Groups Guess what it would be called with only 2 phosphates? 1 phosphate? How could it release energy?
Energy Release & ADP Adenosine Diphosphate A PiPi Pi Adenosine Molecule 2 (di-) Inorganic Phosphate molecules 1 Free Inorganic Phosphate Molecule Energy released when bond breaks energy When the terminal bond is broken energy is released. 1 phosphate – adenosine monophosphate Adenosine Triphosphate Inorganic Phosphate molecules
Adenosine triphosphate (ATP) Main energy carrier molecule in the body (and all living things). ATP is used to transfer (links) the energy released (catabolic) from cellular respiration to synthetic pathways (anabolic) and other cellular processes where energy is required Carbon dioxide and water Glucose and oxygen ATP ADP +Pi Amino acids Protein CELLULAR RESPIRATION ENERGY TRANSFER SYNTHETIC PATHWAY energy Which cells/processes need energy?
Uses of ATP in cells are: Image source: Sperm cell Image source: Liver cell Muscle cell Image source: Nerve cell Image source: Muscle contraction Driving chemical reactions Active transport Synthesis of e.g. protein Transmission of nerve impulses
Bioluminescence Demonstration - Luminescence is emission of light by a substance not resulting from heat; it is thus a form of cold body radiation
ADD ATP
George McGavin Edith Widder
Fluoro Fish
Fluoro Fish Taiwan's leading fluorescent fish industry has developed fluorescent fish that only glow from their blood vessels, takes so much ATP unable to have enough energy to reproduce. This technology could be used in the future to detect tumours in other species. The Fluoro Fish are available at pet stores in all the US states, except California. They are marketed as GloFish and are available in Star-fire Red, Sunburst Orange, and Electric Green. They cost between $5-10. The fluorescent zebra fish are created by microinjecting a fluorescent gene construct into fertilized zebra fish embryos. Australia, Canada, New Zealand and Europe prohibit the sale of genetically modified organisms, such as GloFish and they can not be purchased there. Is it morally right to produce glowing fish for fish tanks?
Predict what would happen after 10 minutes? Why?
Demonstrate Questions 1.Calculate the percentage decrease 2.Why is it necessary to use percentage decrease in length in the comparison of the results? 3.What would be a good control for the experiment? 4.Muscle cells use energy for contraction. State one other cell activity that uses energy.
ATP 2 million molecules of ATP per second is needed to satisfy energy requirements for an active cell (such as liver/muscle etc)! How and where is it stored?
Other metabolic pathways (eg. stored as glycogen) Not stored! Rapid turnover of ATP molecules occurs continuously in a cell. Remains quite constant as the same amount is made that is used up (~50g) Cell conserves resources by only producing ATP when needed – it is another example of feedback inhibition. ATP and citric acid inhibit phosphofructikinase Glucose (6C) Intermediate 1 Intermediate 2 Intermediate 3 ATP ADP+ P i ATP ADP+ P i Phosphorylation at step 1 Phosphorylation at step 3 catalysed by phosphofructokinase Irreversible step ATP Citric Acid Cycle & Electron Transport Chain ATP & citric acid inhibit phosphofructikinase! So go back to intermediate 2
Phosphorylation Phosphorylation is process which is enzyme controlled where a phosphate group (Pi) is added to a molecule. ATP ADP +Pi Build-up energy required Breakdown energy released
Phosphorylation Not only making ATP is called phophorylation (remember post translational modifiction of proteins), also when Pi from ATP given to another molecule in a metabolic pathway it makes them more reactive. For example glucose in glycolysis The phosphorylation of molecules to alter their reactivity. ATP ADP +Pi Glucose-6-phosphate (high energy) Glucose
Effect of phosphorylase on phosphorylated substrate Investigation p100 Controls? 3 minute intervals or 10 as shown below
Advantages of ATP Instant source of energy in the cell Universal energy carrier and can be used in many different chemical reactions It is mobile and transports chemical energy to where it is needed IN the cell Releases energy in small amounts as needed
Complete your exit slip before you go ATP Exit cards Draw/label ATP Complete the following equation: ATP _____ + ________ + _______ The process name of adding a phosphate? What happens to the molecules then? Name 3 process that need ATP;