catabolism
breaking down large molecules into smaller products
anabolism
sysnthesize large molecules from smaller products of catabolism
exergonic
release energy (catabolic)
endergonic
require energy (anabolic)
oxidation-reduction reaction
any metabolic reaction involving the transfer of electrons from an electron donor to an electron acceptor
three important carrier molecules
NAD+, NADP+ and FAD
substrate level phosphorylation
involves the transfer of phosphate to ADP from another phosphorlayed organic compound. Happens in glycolysis.
oxidative phosphoylation
in which energy from redox reactions of respiration is used to attach inorganic phosphate to ADP. Happens in the ETC.
photophosphorylation
in which light energy is used to phosphorylate ADP with inorganic phosphate.
catalysts
chemicals that increase the likelihood of a reaction but are not permanently changed in the process.
enzymes
orgainc catalysts
isomerase
rearrangement of atoms within a molecule
apoenzymes
proteins that are inactive if they are not bound to a cofactor.
cofactor
inorganice ions or certain organic molecules called coenzymes
holoenzyme
apoenzyme plus cofactor that form an active enzyme
activation energy
the amount of energy needed to trigger a chemical reaction
hyperthermophiles
organisms that grow best at temps above 80 degrees celcius
optimum temp
in the human body the optimum temp is 37 degree celcius
denature
if temp. rises above a certain point the noncovalent bonds within an enzyme will break thus changing the 3 dimensional shape making it no longer functional
competitive inhibitors
a substrate that are shaped so that they will fit into the enzymes active site and thus prevent the normal substrate from binding. Can be reversed by the other substate being in high concentration.
noncompetitive inhibitors (allosteric inhibition)
do not bind to the active site but instead prevent enzymatic activity by binding to an allosteric site and thus changing the shape of the enzyme making it non longer functional.
allosteric activation
substate that binds to the allosteric site of the enzyme thus changing the shape so that another substrate will be able to bond to the enzyme
glycolysis (Embden-Meyerhof pathway)
first step in the catabolism of glucose via both respiration and fermentation
energy investment stage (glycolysis)
2 molecules of ATP is invested to phosphorylate a 6 carbon glucose and rearrange its atoms to form fructios 1 6-biphosphate
lysis stage (glycolysis)
fructose 1 6-biphosphate are cleaved into 2 3 carbon atoms that are freely convertible to the other
energy-conserving stage (glycolysis)
G3P is oxidized to pyruvic acid yielding 2 ATP molecules. DHAP is also converted to G3P and also oxidized to pyruvic acid yielding 2 ATP.
Glycolysis products
for every glucose molecule it produces 4 ATP and 2 pyruvic acid, which is only a net of 2 ATP since 2 were invested to begin the process.
cellular respiration
metabolic process that involves the complete oxidation of substrate molecules and the production of ATP by a series of redox reactions.
Krebs cycle
series of 8 enzymatically catalyzed reactions that transfer much of this stored energy to coenzymes NAD+ and FAD
feedback inhibition
method of controlling the action of enzymes in which the end-product of a series of reactions inhibits an enzyme in an earlier part of the pathway.
step 1 of Krebs
splitting of the high energy bond between acetate and coenzyme A releases energy to enable the binding of the freed 2 carbon acetate to a 4 carbon compound oxaloacetic acid, forming the 5 carbon compound citric acid.
step 2 of Krebs
the decarboxylations of the Krebs release twon molecules of carbon dixoide for each acetyl-CoA that enters
step 3&4 of Krebs
for every 2 carbon atoms that enter the cycle, two are lost into the environment.
step 5 of Krebs
4 carbon compound left give up energy to ADP making it ATP (substrate level phosphorylation)
step 6 of Krebs
electrons then transferred to FAD and FADH2
step 7 of Krebs
hydration reaction
step 8 of Krebs
NAD takes 2 electrons to make NADH
Electron transport chain
a series of redox reactions during the final stage of cellular respiration.
products of the Krebs cycle
for every 1 glucose you do the Krebs cycle twice resulting in 8 NADH, 2 ATP, 2 FADH2, CO2
ETC location
inner mitochondrial membranes of eukaryotes and in the cytosol of prokaryotes
steps of the ETC
1)their energy is used to pump protons across the membrane
2)pass the electrons to an electon acceptor
3)protons then flow through ATP synthase which synthesizes ATP 4)one molecule of ATP is generated for every 2 protons that cross the membrane.
ATP production of the ETC
Eukaryotes produce 32 ATP and Prokaryotes produce 34 ATP
flavoproteins
intergral membrane proteins in ETC
Ubiquinones
lipid-soluable nonprotein carriers of the ETC
Cytochromes
intergral proteins associated with heme, which is an iron containing, nonprotein pigmented molecule found in the hemoglobin of blood