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1st Law of Thermodynamics The energy of the universe is constant. Energy can be transformed & transferred, but it cannot be created or destroyed. 2 nd Law of Thermodynamics Every energy transfer or transformation makes the universe more disordered. In other words,
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1st Law of Thermodynamics The energy of the universe is constant. Energy can be transformed & transferred, but it cannot be created or destroyed. 2nd Law of Thermodynamics Every energy transfer or transformation makes the universe more disordered. In other words, every energy transfer or transformation increases the entropy of the universe
Based on free energy changes, reactions can be classified as exergonic (energy outward) or endergonic (energy inward). An exergonic reaction proceeds with a net release of free energy. They occur spontaneously. An endergonic reaction is one that absorbs free energy from its surrounds; the energy is stored in the product; they are nonspontaneous.
C6H12O6 + 6O26CO2 + 6H20 + energy 6CO2 + 6H20 + energy C6H12O6 + 6O2
C6H12O6 + 6O26CO2 + 6H20 + energy 6CO2 + 6H20 + energy C6H12O6 + 6O2 6CO2 + 6H20 + energy
A + B + energy → AB There are many types of biochemical reactions taking place in any living system. Which of the following best characterizes the reaction represented above? A) Catabolism B) Oxidation-reduction C) Exergonic reaction D) Endergonic reaction
becomes oxidized C6H12O6 + 6O2 6CO2 + 6H2O + Energy becomes reduced When you compare the formula for photosynthesis with cellular respiration, which is exergonic, which is endergonic? They are both oxidation/reduction reactions. 6CO2 + 6H20 + energy C6H12O6 + 6O2 C6H12O6 + 6O26CO2 + 6H20 + energy
6CO2 + 6H20 + energy C6H12O6 + 6O2 C6H12O6 + 6O26CO2 + 6H20 + energy
CELLULAR RESPIRATION- AN OVERVIEW C6H12O6 + 6O26CO2 + 6H20 + energy
Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
A molecule that is phosphorylated: • Has an increased chemical reactivity; it is primed to do cellular work • Has a decreased chemical reactivity; it is less likely to provide energy for cellular work • Has been oxidized as a result of a redox reaction involving the gain of inorganic phosphate • Has been reduced as a result of a redox reaction involving the loss of an inorganic phosphate
Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
Which of the following statements describes the results of this reaction? C6H12O6 + 6O26CO2 + 6H20 + energy a. C6H12O6is oxidized and O2 is reduced b. O2 is oxidized and H20 is reduced c. CO2 is reduced and O2 is oxidized d. C6H12O6 is reduced and CO2 is oxidized
Starting with one molecule of glucose, the “net” products of glycolysis are: • 2 NAD+, 2 H+, 2 pyruvate, 2 ATP and 2 H20 • 2 NADH, 2 H+, 2 pyruvate, 2 ATP, and 2 H20 • 2 FADH2, 2 pyruvate, 4 ATP and 2 H20 • 6 CO2, 6 H20, 2 ATP and 2 pyruvate
1 2 3 5 4 C6H12O6 + 6O26CO2 + 6H20 + energy
Cube Creature A Cube Creature B The length of each small cube is 1 cm. Cube Creature A is made up of 9 cubes. The large Cube Creature is 3cm in length. Cube Creatures take in oxygen and get rid of carbon dioxide the same way That our cells do. Which Cube Creature is more efficient at gas exchange? A has a 6:1 surface area/volume ratio; B has a 2:1 ratio
Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
Pyruvate (from glycolysis, 2 molecules per glucose) Citric acid cycle Glycolysis Oxidation phosphorylation CO2 NAD+ CoA NADH ATP ATP ATP + H+ Acetyl CoA CoA Where is the energy transfer? CoA Citric acid cycle 2 CO2 FADH2 3 NAD+ 3 NADH FAD + 3 H+ ADP + P i ATP C6H12O6 + 6O26CO2 + 6H20 + energy
H H H H H H H H H e- e- e- e- H+ e- e- H+ H+
Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
The electron transport chain is a collection of molecules (mostly proteins) embedded in the inner membrane of the mitochondrion. The folding of the inner membrane increases the surface area, providing space for thousands of copies of the ETC in each mitochondrion. H Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
Add it up- So far only 4 molecules of ATP have been generated HOW MANY SHOULD WE GET FROM THE COMPLETE BREAKDOWN OF A MOLECULE OF GLUCOSE IN THE PRESENCE OF O2? Where is the energy? C6H12O6 + 6O26CO2 + 6H20 + energy
Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
Chemiosmosis The energy generated by the ETC is used to pump protons (H+) into the intermembrane space. We have a CONCENTRATION GRADIENT (more H+ in the intermembrane space). All along the inner membrane are protein complexes called ATP synthase. What kind of molecule is ATP synthase? This is the ONLY way that the protons can move back through the membrane. ATP synthase uses the energy of the proton flow to power ATP synthesis. This “coupling” of proton (H+) and ATP synthesis is called chemiosmosis. C6H12O6 + 6O26CO2 + 6H20 + energy
Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
There is “compartmentalization” within the mitochondrion. What purpose does it serve? How is a concentration gradient important in the process shown here? What is the significance of the inner membrane being folded? Where is the energy transfer? C6H12O6 + 6O26CO2 + 6H20 + energy
This is probably 26-28 ATP This number is Probably lower
The oxygen consumed during cellular respiration is involved directly in which process or event? • Glycolysis • Accepting electrons at the end of the end of the electron transport chain c.The citric acid cycle d.The oxidation of pyruvate to acetyl CoA
Which process in eukaryotic cells will proceed normally whether O2 is present or not and therefore probably evolved first? • Electron transport • Glycolysis • The citric acid cycle • Oxidative phosphorylation
You have a friend who lost 7 kg (about 15 pounds) of fat on a low carb diet. How did the fat leave her body? • It was released as carbon dioxide and water b. Chemical energy was converted to heat and released c. It was converted to ATP, which weighs less than fat d. It was converted to urine and eliminated from the body
Calculate the Gibbs free energy change (G) for the following chemical reaction: ATP ADP + Pi if the reaction occurs at body temperature and the change in heat (H) = 19,070 cal and the change in entropy (S) = 90 cal/oK ΔG = ΔH – TΔS G = Free Energy H = Enthalpy S = Entropy T = Temperature in Kelvin Δ represents change in value over time
!!! Photosynthesis
Relate the structure to the function- We have compartmentalization again Lots of surface area
Relate structure and function- -At the organ level -At the tissue level -At the cellular level -At the organelle level -At the molecular level