Metabolism and energetics basics Flashcards
at what pH is ATP chemically stable
6-9
hydrolysis of ATP
ATP -> ADP + Pi
ATP -> AMP + PPi
which hydrolysis of ATP releases most energy and when does this occur
ATP -> AMP + PPi
energy crisis signal of cells; intense exercise
Why is ATP hydrolysis so energetically favourable
- relieves electrostatic repulsion between the phosphate groups
- increased entropy; ΔS becomes more positive
- released phosphate ions are hydrated
- high energy bonds of the phosphate group
what is the ΔG of ATP hydrolysis
-31 to -50 kJ/mole
what is the group carrried in high-energy linkage of ATP
Phosphate
what is the group carried in high-energy linkage of NADH, NADPH and FADH2
electrons and hydrogens
what is the group carrie din high-energy linkage of Acetyl CoA
Acetyl group
what is the group carried in high-energy linkage of carboxylated biotin
carboxyl group
what is the group carried in high-energy linkage of S-adenosylmethionine
methyl group
what is the group carried in high-energy linkage of uridine diphosphate glucose
glucose
3 stages of catabolsim of sugars, FA and AA
- glycolysis, beta-oxidation and transamination
- TCA cycle
- oxidative phosphorylation
first law of thermodynamics
energy cannot be created or destroyed, but can be tranformed from one form to another
thermodynamics =
study of energy transfer
types of energy
chemical, potential, mechanical, heat etc
another name for chemical bond energy
Enthalpy
symbol for enthalpy
H
energy when bonds are made =
energy is released
stronger the bond, more energy released
energy when bonds are broken
energy is required
stronger the bond, more energy neeeded
bond energy =
energy required or released during bond breaking and making
energy change of a reaction
ΔH
the sum of energy used when bonds are broken during a reaction and released during the formation of the new bonds
ENTHALPY CHANGE
negative ΔH
when heat is lost from the molecle and released to the surroundings = exothermic
postive ΔH
when heat is taken up from the surroundings = endothermic
which ΔH reactions are more likely to occur
negative ΔH aka exothermic