Biochem 19 HY Flashcards
cellular energy transformations
bioenergetics
if T3 or T4 levels are low where may the problem be occurring
thyroid or pituitary gland
most common cause of angina pectoris
partial coronary artery blockage from atherosclerosis
heart muscles beyond the block from an atherosclerotic plaque receive an inadequate blood flow and oxygen. when do these cells die
when ATP production falls too low
pathway heart relies on for the generation of ATP? percentage of ATP used in a single heart beat
oxidative phosphorylation; 2%
source of energy for cells
ATP
max energy from ATP cleavage thats available to do useful work
delta G
delta G for energy production must be ____ than delta G for energy requiring processes in order for it to be favored
greater
where are the high energy bonds of ATP located
gamma and beta position of the phosphate molecules
ATP hydrolysis is a favorable rxn because the products are more stable. what are the products
ADP and phosphate
enery released from ATP hydrolysis can’t be used directly so what happens
enzymes transfer phosphate to intermediates of the energy requiring rxn (phosphoryl transfer reaction)
delta G is equiv to the chemical bond energy of
products-reactants
delta G value for ATP hydrolysis under standard conditions
-7.3kcal/mol
reaction catalyzed by phosphoglucomutase is reversible and functions in synthesis of glycogen from glucose as well as degradation of glycogen to glucose. If the delta G for conversion of G6P to G1P is +1.65kcal/mol what is the delta G of the reverse reaction
-1.65kcal/mol
equation for ratio of product concentration to substrate concentration at equilibrium
delta G= -RT lm[P]/[S]
delta G value for a reaction like ATP hydrolysis that is exergonic(energy is released)
negative
delta G values that are positive in the forward direction which way is the reaction favored
backwards
reactions with a negative forward delta G
favor this reaction
total amount of heat that can be released from changes in chemical bonds
change in enthalpy of the reaction
increased disorder of the system is described in terms of
delta s or entropy change
high energy phosphate bond of ATP is converted to movement by changing the conformation of a protein is an example of what type of work? ex?
mechanical; muscle contraction
high energy phosphate bond of ATP is used to transport compounds against a concentration gradient describes what type of work? ex?
transport work; Na/K atpase pump
how do plasma memebrane ATPases and vesicular ATPase used the chemical bond energy of ATP
phosphorylates transport protein and changes its conformation
when enegy intake to the body exceeds energy expended how is the difference stored
as fat
