ATP Flashcards
(29 cards)
What is the structure of ATP?
Pentose sugar(ribose) + Nitrogenous base(adenine)+ 3 phosphate groups
How is ATP used to perform cellular work?
By exergonic reaction of hydrolysis of ATP
endergonic reaction of ATP donating its phosphate group to another molecule by a process known as phosphorylation
What are 3 phosphate groups of ATP called?
alpha,beta and gamma
High energy bonds are between alpha and beta + Beta and gamma
Which form ofP is more unstabilized?
Phosphorylated ATP is more unstable
What is the hydrolysis reaction of ATP?
ATP+H2O→ADP+Pi+ free energy
Under cellular reactions, how much energy does hydrolysis of one mole of ATP yield?
-14kcal/mol
How does sodium- potassium pump function with the energy coupling reaction of ATP?
What is the first law of thermodynamics?
The total energy of the universe is constant; the energy cannot be destroyed or created but it can be transferred and transformed.
What is the second law of thermodynamics?
Every transfer of energy involves loss of energy, resulting in a more disordered system, thus no energy transfer is efficient.
What kind of energy is resulted in every transfer of energy or transformation
Unstable energy
eg.heat energy
What is potential energy?
The energy that has the potential to do work. Chemical bonds of macromolecules have potential energy so that energy is released by the breakdown of these bonds to do work for our body.
What is free energy?
According to the second law of thermodynamics, every transfer of energy result in the loss of energy in the form of unusable energy. Free energy is the measure of the USABLE energy, the energy that is able to do work.
Free energy equation
ΔG° = ΔH° - TΔS°
ΔH°=enthalpy (Change in energy between energy transfer)
ΔS°=entropy (the disorder of the system)
What is exergonic reaction?
Energy is released in the reaction.Therefore,products have less free energy than reactants.
ΔG°<0 (Negative) and reaction is spontaneous
What is endergonic reaction?
The chemical reaction requires input of energy.Therefore the free energy of the products is higher than the reactants.
ΔG°>0 (Positive) and reaction is nonspontaneous
What is the state of equilibrium?
Lowest free energy and highest entropy
What happen to the cells when they reach the state of equilibrium?
They die b/c they don’t have enough free energy to carry out the functions.
Do cells reach the state of equilibrium?
No, bcuz cells are in open system and obtain the energy from their surroundings and cell cycles alsoreogele the energy from a reaction to another.
Why is phosphorylated form of ATP is unstable?
Bcuz phosphate groups have negatively charges and hence repel one another, the repulsion makes ATP unstable.
The negatively charges repel one another, hence requiring energy to bond them together and releasing energy when these bonds are broken.
What happen when biological macromolecules are broken?
During a catabolic reaction, some bonds are broken and others are formed, releasing energy and resulting in lower-energy products.
Organisms are _____systems
Open systems
They receive energy from light or chemical food and transform them to heat and other energy in their surroundings.
At the equilibrium, free energy is ____ & ____ is maximum
Minimum
Entropy
Every energy transformation,decreases the amount of usable energy.True or False?
True
The entropy of the organisms____ as the disorderness of the surroundings____.
Decreases the entropy
Increases the disorderness
Simpler molecules are obtained from the complex molecules breakdown ——> organisms entropy lowers but the breakdown of molecules produces unusable energy and hence increase the entropy of the universe
