FCELL- metabolism, ATP and glycolysis Flashcards
why study metabolism
metabolic diseases
disease state changes the way the body uses food
understand a disease n=may need to know how the body normally deals with nutrients’ can use changes in metabolism to aid diagnosis and follow treatment
what is a catabolic process
the breakdown of complex molecules to release energy
what is an anabolic process
synthesis of new molecules from less complex components
describe energy provision to the body
most catabolism consists of reactions that extract energy from fuel stuffs and converts it to ATP
total amount from hydrolysis - 65kj/mol
how much do we use at rest - 40kg/24 hours
excercise - 0.5kg / minute
total body content of ATP is 100g
what are cofactors
NAD/ FAD - used as electron carrier for oxidation / reduction reactions
what is the overall pathway of glycolysis
glucose split into G-6-P - requires energy - maintains glucose gradient and traps glucose in the cell - irreversible
G6P is then turned into fructose 6 phosphate - requires energy
fructose 6 phosphate is turned into fructose 1,6 - bisphosphate - split into DHAP and GAP
turned into phosphoenol pyruvate - NAD+ is turned into NADP, ADP turned into ATP
phosphoenol pyruvate is turned into pyruvate - ADP turned into ATP
what enzymes are involved in glycolysis
hexokinase - Glucose to G6P
phosphofructokinase - regulated fructose 6 phosphate to fructose 1,6-bisphosphate
pyruvate kinase- converts phosphoenol pyruvate to pyruvate
how can glycolysis be regulated
reversible binding of allosteric effectors
covalent modification
transcription
outline the products of metabolising galactose and fructose
galactose goes to glucose
fructose goes to fructose 6 phosphate / DHAP / GAP in the liver
what is different in exercising muscles
produces lactate
anaerobic respiration
how is hexokinase regualted
regulated by G6P - inhibits further conversion of glucose to G6P preventing too much glucose entering the pathway
how is phosphofructokinase regulated
ATP, Citrate, H+, end products of glycolysis
if there is enough ATP = no need to glycolysis to take place
how is pyruvate kinase regulated
by ATP
which is the most important control point and how is it regulated
PFK - high concentration of ATP inhibits by lowering affinity for fructose 6 phosphate
also inhibited by low pH
why is the liver not inhibited by G6P
the liver has glucokinase
