Name ____________________________________ Date ____________ Period _____
STAGE 1: GLYCOLYSIS
Raven Ch. 9
Big Idea 2: BIOLOGICAL SYSTEMS UTILIZE FREE ENERGY AND MOLECULAR BUILDING
BLOCKS TO GROW, TO REPRODUCE AND TO MAINTAIN HOMEOSTASIS.
Essential Knowledge:
 Cell membranes are selectively permeable due to their structure.
 Growth and dynamic homeostasis are maintained by the constant movement of molecules across membranes.
 Eukaryotic cells maintain internal membranes that partition the cell into specialized regions.
 All biological systems from cells and organisms to populations, communities and ecosystems are affected by
complex biotic and abiotic interactions involving exchange of matter and free energy.
 Homeostatic mechanisms reflect both common ancestry and divergence due to adaptation in different
environments.
Glycolysis
 Breaking down _____________________
 “glyco – lysis” (splitting sugar)



ancient pathway which harvests energy
 where energy transfer __________________
 transfer energy from _________________ to _______
 still is starting point for ALL cellular respiration
but it’s ___________________
 generate only __________ for every ___________
occurs in ___________________
ATP
In the cytosol? Why does that make evolutionary sense?
__________________________________________________________________________________________
Evolutionary perspective
 Prokaryotes
 first cells had no organelles
 Anaerobic atmosphere
 life on Earth first evolved without free oxygen (O2) in atmosphere
 energy had to be captured from organic molecules in absence of O2
 Prokaryotes that evolved glycolysis are ancestors of all modern life
 ALL cells still utilize glycolysis
What does it mean that enzymes of glycolysis are “well-conserved”? _________________________________
__________________________________________________________________________________________
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Glycolysis Overview: 10 reactions
Purpose: convert ______________ (6C) to ______________ (3C)
Produces: __________ & __________
Consumes: __________
Net yield: __________ & __________
Glycolysis summary
____________________________
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Substrate-level Phosphorylation
 In the last steps of glycolysis, where did the P come from to make ATP?
 the sugar substrate (PEP)
Energy accounting of glycolysis
 Net gain = _____________ + _____________
 some energy investment (-2 ATP)
 small energy return (4 ATP + 2 NADH)
 1- 6C sugar  2- 3C sugars
Is that all there is?
 Not a lot of energy…
 for 1 billon years+ this is how life on Earth survived
 no O2 = slow growth, slow reproduction
 only harvest 3.5% of energy stored in glucose
 more carbons to strip off = more energy to harvest
O
But can’t stop there!

Going to run out of __________________
 without regenerating NAD+, energy production would stop!
 another molecule must accept H from NADH
 so NAD+ is freed up for another round
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How is NADH recycled to NAD+?
 Another molecule must accept H from NADH
Fermentation (anaerobic)
 ______________________________
Examples:
________________________
________________________

______________________________
Examples:
________________________
________________________
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Alcohol Fermentation
 ___________________
 at ___________________, kills yeast
 can’t reverse the reaction
Lactic Acid Fermentation
 ___________________
 once O2 is available, lactate is converted back to
________________ by the liver
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