Mod7

Question 1

Chemiosmotic hypothesis

Answer 1

Etc transforms the energy in the electrons into a proton gradient - higher concentrations of protons in the intermembrane space and lower levels in the matrix

Question 2

Proton-motive force

Answer 2

Generated by the electrochemical gradient of protons - force or energy used to synthesize atp

Question 3

Malate Aspartate Shuttle

Answer 3

• in heart and liver
• used to bring the electrons from NADH into the mitochondrial matrix from cytosol
• electrons from NADH used to reduce oxaloacetate to malate in the cytosol
• transporter in inner mitochondrial membrane transports malate into matrix (in exchange for alpha-ketogluatarate)
• malate oxidized back to oxaloacetate, producing NADH (nadh enters the etc)
• oxaloacetate crossed the inner mitochondrial drill membrane by u der going a transamination rxn to form aspartate
• oxaloacetate regenerated in the cytosol so it can bring more electrons from nadh into the mitochondria

Question 4

Cellular respiration

Answer 4

• Collective activities of the citric acid cycle and oxidative phosphorylation
• regulated by the need for atp

Question 5

Protons required to flow through ATP synthase for synthesis of one ATP

Answer 5

3

(1 proton required to transport 1 atp across inner mitochondrial membrane into cytosol)

10 protons pumped during NADH electron flow

Question 6

Number of ATP molecules produced by every NADH entering the ETC

Answer 6

2.5 ATP

Question 7

Number of ATP molecules produced by every FADH2 entering the ETC

Answer 7

1.5 ATP

Question 8

Net ATP yield from glucose oxidation

Answer 8

30 ATP (26 coming from oxidative phosphorylation)

Question 9

ATP yield from anaerobic metabolism through glycolysis alone

Answer 9

2

Question 10

ETC activator

Answer 10

ADP

If atp synthase stops etc stops

Question 11

Binding-change mechanism

Answer 11

The cycling of the three beta subunits in ATP synthase between three conformational states: TOL (tight open loose) the active site in each state performs a different function.

B subunit conformation changes caused by the rotation of the y subunit

Question 12

Cellular respiration

Answer 12

The set of metabolic reactions and processes that convert biochemical energy in fuels into ATP. This includes the citric acid cycle, etc, and oxidative phosphorylation

Question 13

Chemiosmotic hypothesis

Answer 13

The proton gradient generated by the energy released during electron electron transport results in a proton motive force, which allows ATP synthase to generate ATP from ADP and Pi

Question 14

Cytochromes

Answer 14

Proteins that contain a heme moiety and function in electron transfer

Question 15

Proton motive force

Answer 15

The force that promotes movement of protons across membranes from the side of highest concentration to the side with lower concentration

Question 16

Reactive oxygen species

Answer 16

Chemically reactive and unstable atoms or molecules that contain oxygen and which readily react with other molecules

Question 17

Redox potential

Answer 17

The measure of the tendency of a molecule to acquire electrons and become reduced

Question 18

2 products of the electron transport chain

Answer 18

Water and ATP

Question 19

Cellular component that the electron transport chain complexes are located in

Answer 19

Inner mitochondrial membrane