CELLULAR RESPIRATION QUESTION 1989:		L. PETERSON/AP BIOLOGY
	Explain what occurs during the Krebs (citric acid) cycle and 
	electron transportn by describing the following:
	a.  The location of the Krebs cycle and electron transport chain 
	     in the  mitochondria
	b.  The cyclic nature of the reactions in the Krebs cycle
	c.  The production of ATP and reduced coenzymes during the cycle
	d.  The chemiosmotic production of ATP during electron tranpsort


  STANDARDS:   3 points Maximum for each of the four sections
          1 point for any of the following:
  LOCATION
  ___Description of internal structure (compartmentalization) of mitochondrion
  ___Krebs in matrix (inner or M compartment)
  ___Krebs' enzymes mostly dissolved in matrix
  ___ETS in cristae (inner membrane)
  ___ETS components are embedded in the inner membrane
  5 pts   MAX 3
  CYCLIC NATURE OF KREBS
  ___Acetyl CoA (C2) starts Krebs
  ___C2 joins with OAA (C4) to form citric acid (C6)
  ___2 CO2 removed during Krebs
  ___OAA is recycled or overall cycle concept (diagram OK)
  ___Position of Krebs in Aerobic Respiration (2 cycles/glucose, uses products of 
         glycolysis)
  5 pts   MAX 3
  PRODUCTION OF ATP AND REDUCED COENZYMES
  ___ 1 ATP/cycle
  ___NADH and/or FADH2 formed (or NADH2, NADH + H+, NAD red)
  ___Amount of NADH (3) and/or FADH2 (1) per cycle
  ___ATP formed from released energy; substrate level phosphorylation
  ___ATP specific reaction: Succinyl CoA -> Succinic Acid; GTP --> GDP
                                   ADT  ->   ATP
  ___NADH or FADH2 formed by H or e-
  6 pts   MAX 3
  CHEMIOSMOTIC PRODUCTION OF ATP
  ___Electron transfer (redox) through carriers; O2 final acceptor
  ___Gradient drives ATP formation or battery (electrochemical, charge separation, etc.)  
  ___Protons pumped to inter-membrane space; 
     proton carriers alternate w/electron carriers;
     charge separation; gradient established;
     lowers pH in inter-membrane space; 
     + between membranes; - matrix
  ___Inner membrane impermeable to H+ except for and/or proton channel 
         (ATP synthetase; ATPase) is permeable
  ___ATP synthetase structure F0 + F1
  ___Specifics of # of ATPs formed (ETS = 32 ATP; 2 ATP/FADH2; 3ATP/NADH)
  6 pts   MAX 3