Bionergetics

energy currency

what is the primary role of ATP in living systems?

isothermic

biologic systems are essentially what type of systems regarding temperature?

metabolic rate

what term describes the rate of energy release in metabolism?

useful energy for work

what does Gibbs free energy change (AG)?

transferred or transformed

according to the 1st law of thermodynamics, energy can only be what?

total entropy increases

what does the 2nd law of thermodynamics state about entropy?

power living processes

what is the primary function of biologic systems in relation to energy?

marasmus

what condition is characterized by malnutrition with an energy imbalance?

free energy

what is useful energy in a system called?

disorder

living systems maintain order by increasing ________ in their surroundings

spontaneous reaction (exergonic)

what does a negative Gibbs free energy change (AG < 0) indicate?

Non-spontaneous reaction (endergonic)

what does a positive Gibbs free energy change (AG > 0) indicate?

system is at equilibrium

what does AG = 0 signify for a system?

AG = ΔH – TAS

what is the formula relating Gibbs free energy change to enthalpy and entropy

total change in internal energy (ΔE)

in biochemical reactions, what is AH approximately equal to?

absolute temperature

what does ‘T’ represent in the AG = ΔH – TAS equation?

entropy

what does ‘S’ represent in the AG = ΔH – TAS equation?

enthalpy

whaat does ‘H’ represent in the AG = ΔH – TAS equation?

1M concentration, pH 7.0, 25 degrees celcius

what are standard conditions for AG degree measurement?

AG° = −RT ln Keq

what is the relationship between standard free energy (AG°) and the equilibrium constant (Keq)?

by coupling to exergonic processes

how do endergonic reactions proceed in living systems?

synthetic reactions

what is an example of an endergonic process?

a shared intermediate molecule

what is a common mechanism of coupling reactions?

a common intermediate

in the coupling mechanism A + C > B + D, what does ‘I’ represent?

common intermediate

what does the symbol ‘I’ represent in the reaction A + C > B + D?

catabolism

what is an example of an exergonic process?

an exergonic reaction

what drives an endergonic reaction when coupled?

net exergonic outcome

what is the overall requirement for a coupled system involving endergonic and exergonic reactions?

respiratory control

what is an example of coupling where oxidative rates are regulated by product utilization?

the energy released from A > B

what drives the conversion of C > D in the coupled reaction A+C> I > B+D, if A>B releases energy?

ATP

what is the principal high-energy intermediate in living cells?

catabolic and anabolic

what two types of reactions does ATP efficiently link?

adenine and ribose

what are the components of adenosine?

as a magnesium complex (Mg2+ - ATP)

how does ATP function in cells regarding magnesium

from exergonic to endergonic processes

what is the main role of ATP in transferring energy?

high-energy phosphate bond

what does the symbol of ~P denote?

intermediate position in energy transfer

why is ATP considered a universal energy intermediary?

converted to AMP + PPi

what happens to ATP when higher energy is needed beyond ADP conversion?

efficient energy capture and transfer

what is the significance of ATP’s intermediate AG’ value?

Adenosine Triphosphate (ATP)

what is the primary energy currency in all living cells?

Energy-producing and energy utilizing processes

what does the ATP/ADP cycling rapidly link?

rapid turnover

although the total ATP/ADP pool is small, what allows it to sustain life processes?

oxidative phosporylation

what is the main quantitative source of ATP in aerobic organisms?

glycolysis

which process produces two molecules of ATP per molecule of glucose converted to lactate?

succinate thiokinase step

which step in the citric acid cylce directly generates one ATP (or GTP)?

Glucose-6-phosphate

which of the following is NOT a high-energy phosphate compound?

anhydride bond

what type of bond is found in 1,3-bisphosphoglycerate, contributing to its high energy?

enol phosphate bond

what type of bond is found in phosphoenolpyruvate, contributing to its high energy?

high-energy phosphates

what are phosphoguanidines example of?

synthesize UTP, GTP, CTP from diphosphates

what is the role of nucleoside diphosphate (NDP)

ATP + AMP = 2ADP

what reaction is catalyzed by Adenylyl kinase (Myokinase)?

maintains adenine nucleotide balance

what is the significance of adenylyl kinase in energy homeostasis?

participate in phosporylations

what is the function of UTP, GTP, CTP in the cell?

Nucleoside monophosphate (NMP) kinase

what specific kinase catalyze the formation of NDP from monophosphates?

Acetyl-CoA

which of the following is a high-energy compound that is a thiol ester?

temporary storage forms of high-energy phosphate

what are phosphagens?

vertebrate skeletal muscle, heart, and brain

where is creatin phosphate primarily found?

phosphagens rapidly donate phosphate to regenerate ATP

what happens when ATP levels drop, regarding phosphagens?

creatine kinase reaction

what reaction regenerates ATP from phosphagens?

maintain stable ATP/ADP ratio

what is the purpose of replenishing phospagens when ATP levels rise?