| Question |
Answer |
| oxidative phosphorylation definition |
the process by which energy derived from a series of oxidation/reduction reactions (that use NADH as electron donor and oxygen as ultimate electron acceptor) is used to phosphorylate ADP |
| what does the matrix of the mitochondria contain |
pyruvate DH, most CAC enzymes, and other enzymes |
| what does the inner membrane of the mitochondria contain |
electron transport system, ATP synthase complexes and specific carrier proteins called antiporters and synporters; impermeable to all molecules not carried by transporter protein |
| outer membrane of mitochondria |
permeable to most small molecules due to channel proteins called porins |
| cristae of mitochondria |
invaginations that serve to increase surface area of inner membrane |
| intermembrane space |
dlectrochemically distinc from matrix (because inner membrane is impermeable); electrochemically equivalent to cytosol (because of porins) |
| reducing equivalent |
designates a single electron equivaltent in a redox reaction |
| types of redox reactions |
1.direct electron transfer-transfer of e- between metal ions 2.transfer in the form of H atom-flavin linked DHs such as succinate DH 3.electron transfer in the form of hydride ion; NAD-linked DHs such as malate DH 4.replacement of CC or CH with CO,CS,CN |
| standard reduction potential |
a measure of a compounds propensity to donate electrons. Eo, which is measure using molecular hydrogen (H2) as the reference standard |
| how is standard reduction potential measured |
measuring the voltage difference between a H half cell and a half cell containing a 1M solution of the test compound and its conjugate oxidized form |
| Eo<0 |
if test compound donates electrons more readily than H2, electrons will flow from test cell to reference cell (the voltage will be negative) |
| Eo>0 |
test compound donates its electrons less readily than H2, electrons flow from reference cell to test cell (the voltage will be positive) |
| lower Eo |
the lower the Eo the greater the tendency to lose electrons |
| reclinamonas |
all present day mitochondria contain a subset of the genes present in reclinamonas mitochondria |
| what does the ETS consist of |
4 multiprotein respiratory complexes and two carriers that shuttle reducing equivalents between the complexes |
| ETS complex 1 (NADH-Q oxidoreductase) |
34 subunits, oxidizes NADH, reduces coenzyme A; prosthetic groups are flavin mononucleotide (FMN) and iron-sulphur (Fe-S) clusters, pumps 4 protons |
| ETC complex 2 (Succinate-Q reductase) |
4 subunits, oxidizes succinate, reduces Q, prosthetic groups are flavin adenin dinucleotide (FAD) and FE-S clusters, does not pump protons |
| ETS complex 3 (Q-cytochrome c oxidoreductase) |
10 subunits, oxidizes Q, reduces cytochrome; prosthetic groups are Fe-S clusters, Q, and hemes bH, bL and c1 (Fe-containing porphorin rings) pumps 2 protons |
| ETS complex 4 (Cytochrome c oxidatase) |
10 subunits, oxidizes CytC, reduces 02; prosthetic groups are hemes a and a3 and copper-containing porpherin rings CuA and CuB, pumps 4 protons |
| Coenzyme Q |
hydrophobic compound that diffuses freely in lipid bilayer, fully reduced form (QH2) carries 2 reducing equivalents, shuttles reducing equivalents from complex 1&2 to complex 3 |
| cytochrome C |
small soluble protein loosely associated with cytosolic side of inner membrane; heme prosthetic group; shuttles one elctron at a time to complex 4 |
| ATP synthase complex |
complex acts like turbine, a,b2, sigma, alpha and beta subunit stationary, and the co ring and attached gamma and epsilon subunits rotate |
| what does the beta subunit bind |
adenine nucleotides, has ATPase activity and is the site of ATP synthesis |
mr. charles11
