Unit C: Cellular Respiration

Nota:

• Glucose is stored as cellulose and starch in plants and it is stored as glycogen in animals. There are 2 types of CR: -Aerobic -Anaerobic

1. Anaerobic CR = NO OXYGEN

   Nota:

   • ALL organisms perform anaerobic cellular respiration - no special organelle is required.
   1. Step 1: Glycolysis

      Nota:

      • Remember that this only yields 2 ATP in total
   2. Step 2: Fermentation
      1. Alcoholic Fermentation

         Nota:

         • 1) Water is added to pyruvate and a CO2 is expelled which creates a 2 carbon compound (Acetaldehyde) 2) NADH loses its electrons and becomes NAD+ as it reduces acetaldehyde into ethanol
         1. Used in Brewing, Wine Making, and Baking

            Nota:

            • Also used in making Soy Sauce, Chocolate, Saki, Vinegar, and Biofuel
      2. Lactic Acid Fermentation

         Nota:

         • 1) Pyruvate from glycolysis is reduced into lactic acid by NADH as it is oxidized into NAD+
         1. Accounts for Sore muscles, Rigor Mortis, Yogurt & Sauerkraut
      3. *remember that there are 2 pyruvates, so these rxns occur twice!
   3. *The goal is to get the NAD+ back in order to keep performing glycolysis
2. Aerobic CR = OXYGEN

   Nota:

   • Organisms must have mitochondria in order to perform aerobic cellular respiration
   1. Step 1: Glycolysis

      Nota:

      • 1) A glucose molecule is split into 2 PGAL molecules by the oxidation of 2 ATP (Energy investment) 2) NAD+ and ADP are reuced into NADH and ATP as they take electrons from the PGAL and become Pyruvate *this happens twice so a total of 2 NADH are produced & 4 ATP (2 ADP per PGAL)
      1. *in cytoplasm
      2. Energy input & payoff
         1. Results in 2 ATP, 2NADH and 2 Pyruvates
      3. not very efficient

         Nota:

         • - You only get 2 ATP from it
   2. Step 2: Pyruvate Oxidation

      Nota:

      • 1) Pyruvate moves into the mitochondrial matrix and 1 carbon (CO2) is removed 2) NAD+ is reduced into NADH and an intermediate acetic acid is the result 3) Coenzyme A attaches to the acetic acid which forms Acetyl CoA
      1. *in the mitochondria
      2. Results in 2 NADH and 2 Acetyl CoA
      3. *Happens twice b/c there were 2 Pyruvates made in glycolysis
   3. Step 3: Kreb's Cycle
      1. *in the matrix
      2. *happens twice because 2 acetyl CoA's were made
      3. Results in 6 NADH, 2ATP and 2 FADH2 & releases 4 CO2
   4. Step 4: ETC & Chemiosmosis

      Nota:

      • 1) NADH and FADH2 enter the electron transport system in the inner mitochondrial membrane 2) They drop off their electrons & as they are transferred, an H+ is transported into the intermembrane space (this causes a very high concentration of protons) 3) The electrons are transpired to oxygen and join with a proton to produce water 4) The protons in the intermembrane space down their concentration gradient through ATP Synthase and facilitate the creation of ATP *The NADH that was made in glycolysis has to be converted into FADH2 in order for it to go through the mitochondrial membranes
      1. occurs in the mitochondria
      2. *where the most ATP is directly created
      3. NADH = 3e- --> 3 ATP FADH2 = 2e- --> 2 ATP
      4. Oxygen = terminal electron acceptor
      5. Results in 24ATP
3. Electron carriers involved = NADH and FADH2

   Nota:

   • NADH is oxidized into NAD+ FADH2 is oxidized into FAD+
4. 36% Efficient

   Nota:

   • Only 36% of the energy in glucose is converted into ATP - the rest is lost as heat (this is used by warm-blooded organisms to stay warm)

1. MOTION
2. TRANSPORTING IONS & MOLECULES
3. BUILDING MOLECULES
4. CONTROLLING RXNS
5. BIOLUMINESCENCE

Nota:

• -Double layered organelle that produces lots of ATP

1. Mitochondrial Matrix: protein rich liquid filling the inside of the organelle

   Nota:

   • *Pyruvate oxidation, the Kreb's Cycle, and Electron Transport and Chemiosmosis occur here
2. Intermembrane Space: fluid filled space between inner & outer membranes

1. Creatine Phosphate

   Nota:

   • = source of phosphate *more phosphate = more ATP? = harder workout session
2. Carbon Monoxide

   Nota:

   • -Binds to RBCs to prevents O2 transport which means there is no terminal electron acceptor -CR stops = death
3. Cyanide & Hydrogen Sulfide

   Nota:

   • Prevent electron transfer in the ETS -body can't survive off of 2 ATP from glycolysis so you die