Unit 3 Flashcards
define metabolism
all of an organisms chemical reactions
metabolic pathway
begins with a specific molecule, which is then altered in a series of defining steps, resulting in a certain product
catabolism
breaking down larger molecules into smaller ones
anabolism
building up larger molecules from smaller ones
kinetic energy
energy of motion
potential energy
stored energy
thermodynamics
study of relationships among various forms of energy
1st law of thermodynamics
energy cannot be created or destroyed
2nd law of thermodynamics
energy transfer or transformation increases the entropy of the universe
true or false? all energy conversions are 100% efficient
false
biological organisms need a constant input of _____________ to maintain their low entropy
energy
H = G + S
Total energy (H, enthalpy) = usable energy (G, Gibbs free energy) + unusable energy (S, entropy)
if delta G is negative
the reaction is spontaneous, exergonic
exergonic
energy is released
if delta G is positive
the reaction is not spontaneous, endergonic
endergonic
requires energy
if delta G is zero
reaction is at equillibrium
delta G for hydrolysis of ATP
-7.3 kcal/mol
catalyst
substance that speeds up the rate of a chemical reaction
catalysts lower…
activation energy
physically, catalysts…
bring molecules close and bend bonds
enzyme-substrate interaction
-substrate and enzyme make a temporary union
-substrate is inserted into the active site
-the process is irreversible
enzymes need optimal conditions such as
temperature, salt, pH
irreversible enzyme inhibitors
bind to enzyme via covalent bonds
example of irreversible inhibitors
aspirin and some poisons
reversible inhibition
can move on and fall off the enzyme
comptetative reversible inhibition
inhibitor binds at the active site in competition with substrate
noncompetitive reversible inhibitor
bind anywhere except the active site
glucose, fats, and protein are…
long term energy storage molecules
one thing loses an e-
oxidized
one thing gains an e-
reduced
NAD+ –> NADH
oxidized –> reduced
steps of cellular respiration
- glycolysis
- breakdown of pyruvate
- citric acid cycle
- oxidative phosphorylation
where does glycolysis occur?
cytosol
where does breakdown of pyruvate occur?
mitochondria
where does the citric acid cycle occur?
mitochondria
where does oxidative phosphorylation occur?
inner membrane (mitochondria)
how many reactions are in glycolysis?
10
how many ATP are produced in glycolysis?
NET +2 (use 2, make 4)
how many NADH are produced in glycolysis?
2
What carbon chain do you end with in glycolysis?
2 3 carbon chains, pyruvate
how is ATP made in glycolysis?
substrate level phosphorylation
What are the 2 pyruvates converted to during pyruvate dreakdown?
2 CO2 and 2 Acetyl CoA
how many carbons are in acetyl CoA?
2
How many NADH are produced per glucose in pyruvate breakdown?
2
What is reduced in pyruvate breakdown?
NAD+
what is oxidized in pyruvate breakdown?
Carbons
What are the 2 Acetyl CoA converted to in the citric acid cycle?
4 CO2
How many FADH2 are made in the citric acid cycle, per glucose?
2
how many NADH are made in the citric acid cycle, per glucose?
6
how many ATP are made in the citric acid cycle, per glucose?
2
How many complexes are in oxidative phosphorylation
4
What complexes are proton pumps in oxidative phosphorylation?
I, III, and IV
Why do we need to breathe oxygen?
it is the final e- acceptor in the electron transport chain
In oxidative phosphorylation NADH and FADH2 drop off…
electrons
what is oxidized in oxidative phosphorylation?
NADH and FADH2
what is reduced in oxidative phosphorolation?
complexes
In oxidative phosphorylation, the oxygens…
pick up e- and protons to make H2O
as e- move through the electron transport chain in oxidative phosphorylation, free energy…
decreases
What enzyme makes ATP in oxidative phosphorylation?
ATP synthase
