Metabolic pathways

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Metabolic pathways

• Putting it all together

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pathways

• All about energy conversions
• Chemical reactions (REDOX, gain/lose)
• Light to chemical
• Chemical to mechanical
• Follow laws of TD
• Lose some heat, not efficient
• Work against entropy
• Keep cells organized, ALIVE!
• Maintain homeostasis
• Requires energy
• Metabolic pathways
• Organized, coupled, not random
• Products become reactants, assembly line
• Photosynthesis and Cellular Respiration

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enzymes

• End in ase, include substrate in name
• Reduce activation energy
• Induced fit model
• Active site
• Controlled by
• pH
• Temperature
• Amount of enzyme
• Amount of substrate-FEEDBACK INHIBITION
• Allosteric siteshape is everything!

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Photosynthesisa metabolic pathway

• Light Reactions
• Light and water in
• O2, NADPH and ATP out
• NADP reductase, ATP synthase
• Thylakoid membranes
• Dark Reactions
• ATP, NADPH, CO2 in
• ADP, NADP, and Glucose out
• RUBISCO
• Stroma

They Work together!!!
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How did we figure it out?

• 1905 F. F. Blackman
• suggested 2 sets of reactions
• Glucose synthesis requires enzymes
• 1930 C. B. van Neil
• O2 given off by photosynthesis comes from water,
  not CO2
• Hot Oxygen (O18 radioisotope) Tracer
• CO2 H2O C6H12O6 O2 -No O18 given off
• CO2 H2O C6H12O6 O2 -O18 given off

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Cellular Respiration (39)

• Glycolysis
• Glucose and ATP in
• CO2, pyruvate, ATP and NADH out
• Cytoplasm
• anaerobic
• Fermentation
• Glucose in
• Lactate or alcohol and CO2 out
• Cytoplasm
• Anaerobic
• 2.1 efficient

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CR continued

• CAC
• Pyruvate/Acetyl CoA, NAD, FAD, ADP in
• CO2, ATP, NADH and FADH2 out
• Matrix
• ETS
• NADH, FADH2, ADP, O in
• ATP, H2O, NAD and FAD out
• Cristae
• Aerobic

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Proteins/amino acids
Lipids/fatty acids
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Performance Enhancing Drugs Cow farts, Have you
forgotten?

• Drugs like EPO increase RBCs which increase
  oxygen levels. What part of CR is affected by
  this?
• http//vcell.ndsu.edu/animations/etc/movie.htm
• http//www.science.smith.edu/departments/Biology/B
  io231/etc.html
• The bacteria that live in a cows gut live in an
  anaerobic environment. How does this relate to
  their cellular respiration and the methanol they
  produce?