Definition Equation occurs in 2 types Reactants Products

Definition. . . Equation? occurs in. . . 2 types. . . Reactants Products Equation? Reactants Products Extra Bonus Marks – Interestingly. . . What do you remember?

• 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 LO 3

Cellular Respiration Definition – Biochemical process by which energyrich 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: Guess what it would be called • 1 x Adenosine (adenosine) with only 2 • 3 x inorganic phosphate (Pi) phosphates? 1 phosphate? Adenosine Bonds contain energy Pi Pi Pi 3 Inorganic Phosphate Groups How could it release energy?

Energy Release & ADP ¡When the terminal bond is broken energy is released. Adenosine Triphosphate Diphosphate A Pi Pi 1 Free Inorganic Phosphate Molecule Pi 2 (di-) Inorganic Adenosine Molecule Phosphate Energy released molecules Inorganic Phosphate when bond breaks 1 phosphate – adenosine monophosphate

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 Which cells/processes need energy? Carbon dioxide and water ATP energy CELLULAR RESPIRATION Glucose and oxygen Amino acids energy ENERGY TRANSFER SYNTHETIC PATHWAY energy ADP +Pi Protein

Uses of ATP in cells are: Muscle cell Liver cell Image source: http: //www. sccollege. edu Image source: http: //www. agen. ufl. edu Sperm cell Image source: http: //www. dkimages. com Nerve cell Image source: http: //www. dkimages. com • • • 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

Fluoro Fish http: //lem. ch. unito. it/didattica/infochimica/2008_GFP/Fish. html

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?

Glucose (6 C) ATP • 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 (~50 g) • Cell conserves resources by only producing ATP when needed – it is another example of feedback inhibition. • ATP and citric acid inhibit phosphofructikinase Phosphorylation at step 1 Other metabolic pathways (eg. stored as glycogen) ADP+ Pi Intermediate 1 Intermediate 2 Irreversible step ATP ADP+ Pi ATP & citric acid inhibit phosphofructikinase! So go back to intermediate 2 Phosphorylation at step 3 catalysed by phosphofructokinase Intermediate 3 Citric Acid Cycle & Electron Transport Chain

Phosphorylation • Phosphorylation is process which is enzyme controlled where a phosphate group (Pi) is added to a molecule. ATP Breakdown energy released Build-up energy required ADP +Pi

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. . . ATP Glucose ADP +Pi Glucose-6 -phosphate (high energy) • The phosphorylation of molecules to alter their reactivity.

Advantages of ATP Instant source of energy in the cell Releases energy in small amounts as needed It is mobile and transports chemical energy to where it is needed IN the cell Universal energy carrier and can be used in many different chemical reactions

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; • • •