2Note!Please see 3.7 Cell Respiration Core prior to using this presentation.
3Assessment Statements 8.1.1 State that oxidation involves the loss of electrons from an element, whereas reduction involves a gain of electrons; and that oxidation frequently involves gaining oxygen or losing hydrogen, whereas reduction frequently involves losing oxygen or gaining hydrogen.8.1.2 Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP formation.8.1.3 Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs.8.1.4 Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of NADH + H+, the electron transport chain and the role of oxygen.8.1.5 Explain oxidative phosphorylation in terms of chemiosmosis.8.1.6 Explain the relationship between the structure of the mitochondrion and its function.
48.1.1State that oxidation involves the loss of electrons from an element, whereas reduction involves a gain of electrons; and that oxidation frequently involves gaining oxygen or losing hydrogen, whereas reduction frequently involves losing oxygen or gaining hydrogen.
11Phosphorylation 2 ADP + Pi 2 ATP There is anincrease inenergyPhosphorylation uses 2 ATP to add 2 phosphate groups to glucose.This makes the glucose molecule more unstable so it becomes easier to break bonds.The phosphate groups also allow the hexose bisphosphate to bind more effectively with its enzyme.Energy2 ADP + Pi2 ATPTime
12Lysis hexose diphosphate triose phosphate Triose phosphate or TP is an intermediate in many biochemical reactions.The phosphate groups help the TP to bind to its enzyme.
13Oxidation (ATP formation) There are 2 TP molecules made from each glucose.A total of 4 ATP molecules are made.But, we used 2 during phosphorylation.So, we have a net production of 2 ATPNAD+2 ADP + Pireductionoxidation2 ATPNADH+ + H+
19Site of aerobic respiration Pyruvate is further oxidised to release more ATP.Only found in eukaryotic cells.Cells that need a lot of energy will have many mitochondria ( liver cell) or can develop them under training (muscles cells).
20Features of mitochondria Surrounded by a double membrane.Inner membrane folded to form 'cristae'. LSA for ATP production.Space between the two membranes which is narrow creating a place to concentrate H+
21The inner space is called the matrix. It contains the enzymes needed for respiration.especially those of the Kreb’s cycle.An example of compartmentalisation (isolation of substances needed for a particular function)Mitochondria also contain some of their own DNA (mDNA). 76.html
22PPQ Review(a) Draw a labelled diagram showing the structure of a mitochondrion as seen in an electron micrograph (4)(b) Explain the relationship between the structure of the mitochondrion and its function (3)
23(a) Award marks for any of the following clearly drawn and correctly labelled. cristae;inner membrane;outer membrane;intermembrane space;matrix;ribosomes;DNA; max(b) cristae provide surface area for oxidative phosphorylation;inner membrane contains electron transport chains/ATP synthase (whichcarry out oxidative phosphorylation);outer membrane separates the mitochondrion from the rest of the cell;mitochondrial DNA/ribosomes make (mitochondrial) proteins;small volume intermembrane space allows for higher concentrationof protons;matrix has enzymes for the Krebs cycle; max
248.1.4Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of NADH + H+, the electron transport chain and the role of oxygen.
25Link Reaction Decarboxylation - removal of carbon from the pyruvate CoANAD+Carbon forms carbon dioxideCNADH + H+CO22C Acetyl group binds temporarily with Coenzyme ACoACCAcetyl CoA
26Kreb’s Cycle citric acid NADH + H+ FADH2 ATP FAD NAD+ ADP + Pi NAD+ CO2NADH + H+NADH + H+CCCCCNAD+CCO2
27This is a metabolic cycle. Each step requires enzymes to reduce the activation energy.The reactions take place in the mitochondrial matrix.This reaction occurs within the matrix where each intermediate becomes the substrate for the next step.
32TaskReorder the sentences in the booklet to explain the process of chemiosmosis(answers on the next page)
33The inner membrane is folded into cristae and embedded in this membrane are proteinswhich form an electron transport chainReduced NAD+ and FAD are oxidised releasing electrons and H+ ions.The electrons are passed along the chain while theH+ are pumped by the membrane proteins into the inner membrane space.These H+ ions accumulate and their concentration increases.When they diffuse back to the matrix they pass througha membrane protein called ATP synthase.The flow of electrons through ATP synthasedrives an enzyme reaction which converts ADP + Pi to ATP.
34ATP synthase is an enzyme embedded in the cristae membrane. H+create an electrochemical gradient (chemical potential energy).The H+pass through a channel in the enzyme driving the motor.The motor spins bringing together ADP and Pi to produce ATP