Chapter 14 - Energy Generation in Mitochondria (Exam 3)

NADH donates _______-________ _______ for synthesis of ATP

high-energy electrons

where is the specialized chain of electron carriers embedded?

the inner membrane of the mitochondrion

as electrons pass through the series of electron acceptor and donor molecules that forms the electron transport chain, they…

fall to successively lower energy states

the energy released from electrons falling to lower energy states drives…

H+ ions across the membrane

a transmembrane gradient of H+ ions serves as a source of _________ for the phosphorylation of ___ to generate _____

energy, ADP, ATP

electrons are added to O2 molecules and combine with H+ to produce…

H2O

cells obtain their energy by a…

transmembrane-based mechanism

what are the essential requirements for harnessing energy in the form of ATP?

1. an electron transport chain

2. a pump protein

3. an ATP synthase

4. sources of high-energy electrons derived from the oxidation of food and of protons

the pump harnesses the energy of electron transfer to…

pump protons derived from water

the pump creates…

a proton gradient across the membrane

the proton gradient serves as an…

energy store

the proton gradient is used to drive…

the synthesis of ATP by ATP synthase

batteries are powered by…

chemical reactions based on electron transfers

chemiosmotic coupling is the linkage of what three things?

1. electron transport

2. proton pumping

3. ATP synthesis

chemiosmotic coupling used to be called…

chemiosmotic hypothesis

chemiosmotic mechanisms allow the cell to harness…

the energy of electron transfers (works the same way as a battery)

with a battery, chemical energy is converted into…

heat energy

mitochondria are located near sites of high…

ATP utilizatino

what are three characteristics of mitochondria?

1. contain own DNA and RNA

2. constantly change shape and position in the cell

3. position varies between cell types depending on where the majority of ATP is needed

a mitochondrion is organized into…

four separate compartments

protons in water are highly…

mobile

NADH donates its electrons to the…

ETC

protons are pumped across the…

inner mitochondrial membrane

electrons are transferred through how many respiratory enzymes complexes in the inner mitochondrial membrane?

three

NADH dehydrogenase complex accepts electrons from NADH in the form of a…

hydride ion

the orientation of the electron carrier allows for…

electron transfer to drive proton pumping

as an electron passes along an electron-transport chain, it can…

bind and release a proton at each step

what do quinones carry?

electrons within the lipid bilayer

with the help of the 3 respiratory enzyme complexes, enzymes move mainly between…

metal atoms that are tightly bound to the proteins

quinones are the only electron carriers in ETCs that can function without…

being tightly bound to a protein

quinone has a long hydrophobic ______ that confines ubiquinone to the __________

tail, membrane

cytochrome c is an…

electron carrier in the ETC

what small protein contains just over 100 amino acids

cytochrome c

cytochrome c is held loosely on the _______ face of the inner membrane

outerc

cytochrome c is held by an…

ionic interaction

the iron atom in cytochrome c in the bound ______ can carry a ________ electron

heme, single

cytochrome oxidase is a…

protein complex

cytochrome oxidase receives electrons from _________ __ and donates them to ___

cytochrome c, O2

cytochrome oxidase contains how many subunits?

two (I and II)

at its active site where O2 is bound, cytochrome oxidase contains…

a complex of a heme iron atom with a tightly bound copper atom

NADH dehydrogenase or cytochrome oxidase are driven through…

a cycle of three conformations

what is the chemiosmotic mechanism of ATP synthesis called…

oxidative phosphorylation

oxidative phosphorylation involves what two things?

1. consumption of O2

2. addition on a phosphate group to ADP to form ATP

the electrochemical proton gradient across the inner mitochondrial membrane allows _______ synthase to generate _____ from _____ and ___

ATP, ATP, ADP, Pi

the total electrochemical gradient of H+ across the inner mitochondrial membrane is made up of what two things?

1. a large force due to the membrane potential

2. a smaller force due to the H+ concentration gradient

the proton-motive force has what two things that contribute to the driving force of pulling H+ across the membrane?

1. the membrane potential

2. pH