Lectures 1-3 Flashcards
What is Gibbs free energy?
The amount of energy capable of doing work
WHat does a negative G indicate?
the reaction is exergonic and sponatneous
What does a positive G indicate?
A positive G indicates an endergonic reaction that is not spontaneous
What is enthalpy?
Heat content of the system of a reaction
What does a negative enthalpy indicate?
A negative H indicates that the reaction is exothermic, meaning heat was released
What does a positive enthalpy indicate?
Heat was gained into the system, meaning tyhe reaction is endothermic
WHat is entropy?
S, randomness or disorder in a system. increase in entropy means increase in disorder
What are some metabolites that release lots of energy when broken down? Are they exergonic or endogonic?
ATP, NADH, NADPH are all exergonic
WHat is the hydrolysis of ATP? Is it exergonic or endogonic?
ATp becomes ADP. This releases lots of energy. Exergonic
True or False: “Hydrolysis reactions tend to be unfavourable.”
False, they tend to be favourable. Exampe is the hydrolysis of ATP to ADP
Which molecular group is common in biochemical reactionS?
a carbonyl group. This is carbon double bonded to a o.
WHat is aldol condensation?
a stabilized carbanion attacks the carbon of a carbonyl group. This makes a carbon bond between the 2 carbons.
What is a claisen ester condensation reaction?
a carbanion stabilized buy a thioester attacks the carbon of a carbonyl group.This forms a c-c bond between the 2 carbons.
What is a decarboxylation reaction?
a negatively charged oxygen forms a double bound with the carbonyl carbon it is single bond too. this causes a break in the c-c bond between the Carbonyl c and another carbon
WHat is isomerization?
a rearrangement of the molcule occurs as a result of movement of the elctrons in the molecule. Overall, there was no change in oxidative state
What is an example of isomerization?
glucose 6-phosphate to fructose 6-phophate
How do free radicals occur? What do they do?
From homolytic cleavage. They ARE HIGHLY reactive and can cause damage to different biomolecules, like DNA
Why is the hydrolysis of ATP favourable under standard conditions?
the low pH means a proton can be lost
- less charge repulsion/ steric hinderance in products
- the resonace structure of the products is more favourable than the resonace structure of the reactants
Why are the carbons of carbonyl groups considered electron sinks?
This is because they allow for transfers of electrons in the molecule to to occur without changing any charges or oxidative states
