Metabolism Flashcards
what is the definition of metabolism
the sum of all reactions occurring in the cell
what are the two types of metabolism
catabolism and anabolism
what is a catabolic reaction
releases energy, breaks down molecules
what is a anabolic reaction
requires energy, builds bigger molecules from smaller ones
what is free energy
energy released from catabolism that is available to be used in anabolism
what is the change in free energy
delta g
reactions with a negitive delta g are…………
exergonic as energy is released
reactions with a positive delta g are……….
endergonic as energy is absorbed
what stores free energy
ATP
what are the three types of cellular work
transport, mechanical, chemical
what does energy coupling refer to
exergonic reaction providing the energy for an endergonic one
what is ATP hydrolysis
converting ADP to ATP to store energy and ATP hydrolysis to release energy stored in the extra phosphate bond
what is activation energy
energy required for reactant to be at reactive state
what do catalysts do
lower the activation energy and therefore the rate of reaction
is there more change in delta g with a catalyst
no
what are examples of biological catalysts
enzymes, RNA, protein
active site on a enzyme is
where substrate binds to the enzymes
what is a competitive inhibitor
stops the substrate from binding to the active site
what is a non competitive inhibitor
binds to another binding site which changes the shape of the active site so the substrate cant fit
how is the amount of enzyme activity regulated
gene level
how is the activity of enzymes regulated
temporary inhibition of the protein through reversable changes in its shape
What is feedback inhibition
mechanism for turning off biosynthetic pathways, product binds to first enzyme in the pathway which alters it shape temporarily till the product is used
what is the name for the enzymes with many binding sites
allosteric enzymes
what is bioenergetics
flow of energy
