Carbohydrate Metabolism Flashcards
(49 cards)
What is ATP
a high energy nucleotide with 3 phosphate attached to a ribose sugar
what happens when ATP is hydrolised
chemical energy is released losing a phosphate group
is endergonic or exergonic energetically favoured
exergonic
how much ATP is turned over with energy expenditure of 2000Kcal
~45Kg
what is phosphagen pathway used for
explosive, anaerobic, lots of energy quickly
what is mitochondrial respiration pathway used for
slow endurance, aerobic, less ATP slowly
how long would stored ATp last in maximal exercise
~3 seconds
what is myokinase maximal rate of ATP resynthesis
0.9mmol/kg/sec
what is CK maximal rate of ATP resynthesis
2.6mmol/kg/sec
is myokinase reaction aerobic or anaerobic
anaerobic
why is the myokinase reaction favoured
reduced ATP, increase ADP, AMP
PCr outweighs Cr in muscle favouring what
conversion to Cr and ATP
how long do PCr stores last during maximal exercise
~7 seconds
how much larger are PCr stores than ATP
3-4x larger
why does ATP levels not drop a signifcant amount after exercise
doesnt drop below 60% due to enzymes (myokinase and creatine kinase)
why does Pcr have a significant level drop after exercise
it provides the initial explosive demand ~7sec
what change is associated with breakdown of glucose
negative change in Gibbs free energy
why does Glucose have such a huge drop in gibbs free energy
due to multiple complex bonds in hexose sugar
where and how are oligosaccharides broken down into disaccharides
in the villi of small intestine
lactase, maltose and sucrose then break disaccharides into what
monosaccharides
where is glycogen mainly stored
liver (3-7%) and muscle (1-1.5%)
where is glycogen usually located
optimally between thick and thin filaments near mitochondria
what is the process of glycogen synthesis
uridine triphosphate react with glucose to provide energy to build glycogen chain
what enzymes are involved in glycogen synthesis
glycogenin, glycogen synthase, branching enzyme
