Download Preparation for Exam 1

Preparation for Exam 1
Exam 1 will cover chapters 13-17 in your textbook. A major focus for this part of the
course is METABOLIC ENERGY. You were introduced to the following pathways:
glycolysis, Krebs cycle, and oxidative phosphorylation. These are the premiere catabolic
pathways in cells for providing energy. You also were shown anabolic pathways:
gluconeogenesis, glycogen synthesis, pentose phosphate. Glycogenolysis (glycogen
breakdown) fell in the cracks between glycolysis and gluconeogenesis. Study these
pathways by structure and know the intermediates that lead into or otherwise connect the
pathways. Know their structures, not just the names. Know also the major events in
pathway regulation. Know why a cell can survive without oxygen, how the Krebs cycle
becomes a major source of reduced coenzymes to drive electron transport. You should
be able to determine the number of ATPs that are formed when any compound in
glycolysis or the Krebs cycle is broken down to CO2 and H2O. Know how the pentose
phosphate pathway provides the cell with NADPH and allows ribose synthesis from
glucose. Know how the cell uses glycolysis to metabolize fructose, galactose, and
mannose. Know the signals that tell a cell to synthesize or breakdown glycogen. Know
the mechanism of glucagon, insulin in regulating these events. Below are some specifics
that cover this overview.
Review the 6 tutorials. In chapter 13 know high energy compounds, biological
oxidations, coupled reactions, free energy (standard and observed), redox potentials.
Know how to determine free energy from equilibrium constants, from concentrations of
reactants and products at any point in the reaction. Know how to determine electron flow
based on values for electrochemical potential. Know why Krebs cycle and oxidative
phosphorylation are synonymous with aerobic metabolism. Caught in between is
pyruvate, which can go to L-lactate (anaeorbic-mammals), acetaldehyde (anaerobicyeast) or acetyl-CoA (aerobic). Know the difference between decarboxylation and
oxidative decarboxylation. Know the Krebs cycle, its location in the mitochondria, the
points of entry, the reactions taking place, the interface with amino acid metabolism.
Know the anatomy of the mitochondria, the inner membrane space, the matrix, the
various transporters that permit communication between cytosol and mitochondria.
Know oxidative phosphorylation, the entry points for NADH, FADH2, the makeup of the
various complexes, the Q cycle, the FoF1 ATPase (ATP synthase), site-specific
inhibitors, uncouplers, thermogenin, Know the steps in glycolysis that are not reversible.
Know how glucose is made from lactate, from citrate, from aspartate, from glutamate,
from fructose, from glycogen. Know the regulation of glycogen synthesis and
degradation, glycolysis, gluconeogenesis. Know the b and a forms of glycogen synthase
and a and b forms of glycogen phosphorylase. Know the pentose phosphate pathway,
where NADPH is formed, how ribose-5-PO4 is made, how ribose-5-PO4 and xyulose-5PO4 combine to make fructose-6-PO4.