Aims – homework questions 1 – 4, page 81. • To outline why living organisms need to respire. • To describe the structure of ATP. • To see how ATP provides the immediate source of energy for biological processes.
A2 Respiration! Anything you recognise?
Outline why living organisms need to respire… • Two minutes to pair and share….. • What do you think? • Respiration is the process whereby energy stored in complex organic molecules, is used to make ATP. (p 80) • Energy is the ability to ____ and exists as p_____ or k_____ energy. • ATP is a ph___________ nucleotide and is the universal ______ _______. • Now complete gaps on page 1 of booklet.
Complete the gaps… • Energy exists as __1__ or ___2___ energy, large organic molecules containing ___3___ energy. • Energy can’t be ___4___ or __5____. • ATP is a ______6____ ___7_____ and is the _____8___ ___9____ ___10__. • Respiration is the ___11___ whereby ___12___ stored in complex ___13___ ___14___ is used to ___15____ __16__.
AIMS • Energy transfer through food chains. • Structure and role of ATP. • Coenzymes and Respiration. • Glycolysis. • Homework – Use page 86 to complete pages 7, 8, 9 and 10 (table or essay plan) about the structure and function of mitochondria and comparison with chloroplasts.
Energy transfer through food chains….. • Put the cut out words / statements into an energy transfer cycle and copy into your notes – if stuck – see page 81.
Recap the terms metabolism, anabolic and catabolic reactions, page 1 (key def.) • So, which anabolic reactions need energy from ATP? • Are your suggestions the same as on page 80? • Check the table, page 2 and 3 in booklet. • The structure of ATP – make a model (if needed) and draw diagram in space on page 3. • http://www.youtube.com/watch?v=Lx9GklK0xQg&feature=related
AIMS • Starter – Recap yesterday’s new terminology. • ATP cycle • Coenzymes – check homework page 83 questions 1, 2 and 3. • Glycolysis • Introduce Aerobic Respiration with link reaction into Kreb’s Cycle • Homework – Complete questions page 2 in booklet B and Booklet A pages 7, 8, 9 and 10.
The ATP cycle – make notes page 3. 1. ATP is produced by condensation/ phosphorylation, using ADP, Pi, energy, and ATP synthase, and producing water. 2. ATP is hydrolysed back into ADP, Pi and released energy, using ATPase and water. * Where else would you find this nucleotide? Draw outline in own notes or space on page 3
Use a plasticine model to explain to your partner how much energy is released during hydrolysis. Page 81. • Draw Fig. 3 and 4 in your own notes to slip into booklet. • Role of ATP is to provide imm________ energy in s_____, manageable amounts that will not d_______ the cell and will not be w_________. (4 marks) • Is water used up or produced during production of ATP? • Condensation leads to ATP. Give 2 other terms which could describe this reaction. (Hint p_______ and a______)
True or false? • ATP is made of 3 phosphates, adenine and deoxyribose. • A hydrolysis reaction releases energy for cells to do work. • ATP + water releases ADP, Pi and 14.2 kJmol-1. • Respiration releases thermal energy (heat) and chemical potential energy in the form of fats. • ATP is required for active transport, endocytosis, replication of DNA, phosphorylation of chemicals and diffusion. • Now answer questions 1, 2 and 3 page 81.
Coenzymes and Respiration, page 82 • Complete the table summarising the 4 stages of respiration – stage 1, glycolysis is anaerobic and the following 2, 3 and 4 are aerobic. • Regularly H atoms must be removed from substrates by dehydrogenase enzymes, but they find it difficult without a coenzyme to give the H atoms to. • NAD is that coenzyme. (What did the job in photosynthesis?)
Respiration requires us to understand oxidation and reduction. • OIL RIG • Oxidation is? • Reduction is? • Oxidation also involves gaining oxygen and losing hydrogen. • Reduction also involves ______oxygen and..?
NAD, oxidised or reduced – where are the extra H atoms? See page 83 + 5
Check the oxidation / reduction role model! • Complete page 5, including coenzyme A, with simple diagrams and functions. • Answer stretch and challenge page 83. Soaking corn in lime water like the Mexican Indians did.
(Note if not done so) • C6H12O6 + 6O2Energy + 6CO2 + 6H20 • Aims (role) of glycolysisare • to produce pyruvate and NADH for aerobic respiration in mitochondria, • and a little ATP for anaerobic conditions.
Glycolysis occurs in the cytoplasm, • is anaerobic and includes substrate –levelphosphorylation of ADP ATP. • Glyco/lysis breaks down one glucose to produce two pyruvates (which can be used in mitochondria if O2 available) two NADH and two ATP. • See diagram of glycolysis in booklet B, working through with plasticine and beads and then page 84 – correct Fructose-6-P.
Recapping Glycolysis (simply!) • Glycolysis occurs in the ______1______ . • Glycolysis needs ___2____ to start. • Glycolysis breaks one ____3____ into two _______4______. • Glycolysis is ______5_____ so no ______6_____ is required. • Glycolysis uses up __7__ ATP but gains __8_ ATP, so total gain is __9__ but net gain is __10__. • Phosphorylation means……….e.g. • Lysis means………..e.g. • Now cut and stick glycolysis, answer page 7 and check next slide.
Starter - Aim of glycolysis is to i) produce pyruvate and NADH for aerobic respiration in mitochondria, and ii) a little ATP for anaerobic conditions. • Glycolysis involves 1. phosphorylation / 2. lysis of hexose 1,6, bisphosphate / 3. Triose - P oxidation and conversion to pyruvate. • In which part of glycolysis is…. • ATP used up? • ATP produced? • NAD reduced? • Read fermentation and glycolysis page 85 and then answer questions 1 – 4. • http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__how_glycolysis_works.html
When would you like to do a mock F214? Thurs 24th and go through Wed 30th, or homework for then you to mark on the 30th? • AIMS • Remember basic aerobic respiration equation from GCSE? (Note on front of Booklet A) • Check page 2 of booklet B and page 7 in booklet A now. • Remember pyruvate is actively transported into mitochondria. • Check mitochondria structure and function information and page 8 and 9. • Link reaction recap and Kreb’s Cycle. • Oxidative phosphorylation. • Homework – learn aerobic respiration in the mitochondria.
See OHT for diagram. Can you add anything from this one? Intermembrane Space. ?
Now let’s see and note down the aimsof the Link Reaction and Kreb’s Cycle on next slide.
Link Reaction and Kreb’s Cycle is Aerobic • Kreb’s Cycle occurs in the ______ of the ___________. • Kreb’s Cycle produces: • Reduced hydrogen carriers (NADH and FADH). These go to the Electron Transfer Chain where they allow ATP to be produced. • 2 ATP molecules directly from 2 pyruvate (substrate – ____ _______) • 6 waste CO2 for every one glucose oxidised.
Usespyruvate • Produces 3CO2 • Produces __ NADH • Produces __ FADH2 Is a_______. http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__how_the_krebs_cycle_works__quiz_1_.html
Kreb’s Cycle • Work around the cycle using plasticine and page 3 of booklet B. • Answer the questions, on page 2 and 3 of part 2 booklet A.
Pair and Share. • Explain why mature erythrocytes can not carry out the link reaction or Kreb’s. • Aerobic prokaryotes can carry out link, Kreb’s and oxidative phosphorylation. Suggest where these reactions take place in the cell. • Suggest why living cells only have smallamounts of oxaloacetate in their cells. • Why does each stage of Kreb’s need to be catalysed by its own enzyme?
Oxidative phosphorylation • See page 4 of booklet B and next slide. • Animations • In pairs, write down bullet point flow chart. • Compare with next 2 slides. • Role Play! http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter9/animations.html# • http://vcell.ndsu.nodak.edu/animations/atpgradient/movie.htm
Facts about oxidative phosphorylation • Electron Transfer Chain releases energy for oxidative phosphorylation of ___ to ____. • It is aerobic. • It takes place within the _____ ________ of the ____________. • Products are lots of ____ and w_____. • Requirements are i) NADH and ______ to start the system, and ii) o_______ to complete the system.
Oxidative phosphorylation occurs down the _ _ _ within the ____ ___________. ____ and ____ bring H from link + ____ _____ and __________. Dehydrogenases remove __ and split it into __ and e-. e- travel down ETC, their released energy pumping H+ from ______ into ______________ ________. Accumulated H+ rush down their concentration and electrochemical gradient via ___ ________, back into the matrix. Moving H+ ions drive the release of ATP from ___ __________. Oxygen is the final ______ _________, forming w______ with hydrogen protons in the _______.
Some important further facts… • The final electron acceptor in the ETC is ________. • The build up of the proton gradient between the intermembrane space and the ______ , is also an e___________ gradient and a ___ gradient. • The flow of hydrogen ions down ATP synthase is called c__________. • Formation of water (from H ions, from FADH and oxygen in the matrix) can indirectly contribute to the proton gradient because……. Now cut and sort the statements about oxidative phosphorylation.
True or False? • Link/Kreb’s Cycle occurs in the matrix of the mitochondria and is aerobic. • Link reaction requires pyruvate, NADH, CoA, decarboxylase and dehydrogenase enzymes to work. • Acetyl/acetate links with oxaloacetate to produce citrate. • Decarboxylation and dehydrogenation in the cycle initially produce a 5 carbon compound. • The conversion from a 5 to a 4 carbon compound releases enough energy to produce an ATP molecule by oxidative phosphorylation. • 4 NAD and 1 FAD are oxidised during the link and Kreb’s Cycle. • From the point of view of respiration, the aim of the cycle is to produce reduced NAD and FAD for the ETC.
Starter - Oxidative phosphorylation – reminder with animation See page 4 of booklet B and next slide. Animations In pairs, write down bullet point flow chart. Compare with next 2 slides. Role Play! http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter9/animations.html# http://vcell.ndsu.nodak.edu/animations/atpgradient/movie.htm
AIMS – MOCK F214 will be homework for you next Thursday and marked the following Wednesday. • Recap oxidative phosphorylation - complete pages 10 and 11 in booklet A part 2. • Complete “how many ATP produced from 1 glucose?” • Evidence for Chemiosmosis Theory. • Anaerobic Respiration – see booklet C! • Substrate Energy Values. • Linking facts and recycling in respiration. • Comparing Mitochondria and Chloroplasts • Using respirometers to measure rate of respiration or RQ values. • Dominoes or Role Play. • Homework : Booklet A, Part 2 pages 12, 14, 18 – 22, and SAQ 5 and 6 on page 3 of Booklet C.
So, how many ATP are produced per one glucose molecule? 2 2 6 0 0 2 Both reduced NAD and FAD will provide electrons for the ETC. Reduced NAD also provides H ions for the g________. OCR A2 Biology(Heinemann) states that FAD’s H ions combine with O2 in the matrix to form _______.
For each molecule of NAD, up to 2.6 molecules of ATP should be made… • So, how many NAD were reduced starting with one glucose? • 10 • So, how many ATP could be made? • 26 • How many ATP were made by substrate-level phosphorylation (glycolysis and Kreb’s)? • 4 • Now add them together! • Page 91 – list 3 ways this number of ATP is rarely achieved. (You can write your answer in your own notes or on Booklet A Part 2, page 13).
Evidence for Chemiosmosis • Key definition = the d______ of H+ ions across a membrane coupled to the generation of ___ during ______ respiration (oxidative phosphorylation), or photosynthesis (photophosphorylation). • Evidence for Mitchell’s theory page 92/93. • Electron micrographs of mitochondria…….. • Releasing contents of intermembrane spaces of “mitoblasts” allowed…… them to locate the Kreb’s enzymes in the matrix and the ETC enzymes in the inner membrane. 3. Under which 3 conditions was ATP not made by mitochondria? When there was no intermembrane space, no ATP synthase or if ATP synthase was blocked, so no proton flow. 4. Finally, in intact mitochondria, what was true of the pH and potential difference across the inner membrane?
AIMS • Check Homework : Booklet A, Part 2 pages 12, 14, 18 – 22, and SAQ 5 and 6 on page 3 of Booklet C. • Anaerobic Respiration – see homework research and booklet C! • Substrate Energy Values. • Linking facts and recycling in respiration. • Comparing Mitochondria and Chloroplasts. • Exam Questions.
Anaerobic Respiration – check each other’s answers following homework research • Produces lactic acid in muscles. Produces ethanol and ________ ________ in_________. Now complete pages 4 and 5 of Booklet C.
Define the term respiratory substrate…….. page 96. • Respiratory substrate is….. • One mole is the gram molecular mass of a substance, e.g. 180g = 1 mole of glucose. • The more hydrogen atoms there are in a substrate molecule, the more ____ can be produced during respiration. • So, the more H atoms per mole of substrate, the more o________ needed for respiration of that substrate.
Now complete Booklet C called “Exam Question, Evidence for Chemiosmosis and Energy values of different Substrates”, pages 6, 7 and 8. (10 mins) Carbohydrates e.g. glucose / starch / glycogen, fructose and galactose. All are converted to glucose. Why? Protein Lipids
Linking facts in Respiration…. • See Booklet B, pages 7 and 8.
So how does mitochondrial structure help their function? • Use page 86 to help complete gaps on page 8. Let’s check them! • How and why might they be moved around?
1. Linking facts – see pages 7 and 8 in Biochemistry of Respiration booklet B. • 2. Comparing Mitochondria and Chloroplasts – see new sheet to complete. S = similarity and D = Difference
Using a respirometer to measure rate of respiration in invertebrates. • See sheets – this may be an experiment given to discuss experimental technique or to analyse data you have never seen before.