Cellular Respiration Part 1 Pages 90 to 92

Fig. 9-2 Light energy ECOSYSTEM Photosynthesis in chloroplasts CO 2 + H 2 O Cellular respiration in mitochondria Organic molecules +O2+O2 ATP powers most cellular work Heat energy ATP

Summarize Relationship Sunlight provides energy to power photosynthesis – ultimate source of energy Photosynthesis produces glucose and oxygen needed for cellular respiration Cellular respiration produces water and carbon dioxide needed for photosynthesis; it also produces ATP needed to do cellular work

Do plants undergo cellular respiration? Yes! They need ATP for cellular work (building, maintaining, transporting, etc…) just like animals, protists and bacteria

Respiration- Write about it… When you hear the word RESPIRATION, what do you think of? Write your response on the ½ sheet provided. Write at least 2 sentences explaining what respiration means to you. You should use complete sentences in your answer.

How is your breathing related to cellular respiration? Breathing provides the oxygen needed for cellular respiration to occur Breathing eliminates carbon dioxide waste produced by cellular respiration

Complete balanced equation for cellular respiration… C 6 H 12 O O 2  6 CO H 2 O + ATP Glucose + oxygen yields carbon dioxide + water + Energy Is this reaction endergonic or exergonic? ▫Exergonic – releasing energy

Differentiate between life sustaining activities and voluntary activities Life sustaining ▫Heart pumping ▫Breathing ▫Maintain Body Temp ▫Essential for LIFE ▫75% of your daily energy requirements Voluntary ▫Biking ▫Running ▫Swimming ▫Etc.. ▫25% of your daily energy requirements

Redox Reactions (oxidation/reduction) The transfer of electrons during chemical reactions releases energy stored in organic molecules This released energy is ultimately used to synthesize ATP Chemical reactions that transfer electrons between reactants are called oxidation-reduction reactions, or redox reactions

Redox Reactions In oxidation, a substance loses electrons, or is oxidized In reduction, a substance gains electrons, or is reduced (the amount of positive charge is reduced)

Fig. 9-UN1 becomes oxidized (loses electron) becomes reduced (gains electron)

Cellular Respiration - Redox What is being oxidized (gives up electrons) ▫Glucose What is being reduced (takes on electrons) ▫Oxygen

Fig. 9-UN3 becomes oxidized becomes reduced

What is the role of dehydrogenase in cellular respiration? The enzyme that catalyzes the chemical reaction in which one or more hydrogen atoms are removed from a molecule Dehydrogenase

What is the role of NAD+ (NADH)? NAD+ accepts electrons from carbon containing compounds (e.g. glucose) to form NADH NADH then shuttles the electrons to an electron transport chain where they are used to create ATP It is one of the electron carriers of cellular respiration This is a redox reaction What is oxidized? ▫Glucose / carbon compounds What is reduced? ▫NAD+ to form NADH

Fig. 9-4 Dehydrogenase Reduction of NAD + Oxidation of NADH 2 e – + 2 H + 2 e – + H + NAD + + 2[H ] NAD H + H+H+ H+H+ Nicotinamide (oxidized form) Nicotinamide (reduced form)

Fig. 9-5 Free energy, G (a) Uncontrolled reaction H2OH2O H / 2 O 2 Explosive release of heat and light energy (b) Cellular respiration Controlled release of energy for synthesis of ATP 2 H e – 2 H + 1 / 2 O 2 (from food via NADH) AT P 1/2O21/2O2 2H+2H+ 2 e – Electron transport chain H2OH2O

Where is the Electron Transport Chain? The inner membrane of the mitochondria (aka – the cristea)