Terminal Respiration

Question 1

Where is the only site of oxidative phosphorylation in eukaryotes?

Answer 1

The mitochondria

Question 2

Where do NADH and FADH have to be for oxidation in the terminal respiratory system?

Answer 2

Mitrochondiral matrix

Question 3

How does the NADH and FADH that is formed in the cytosol reach the mitochondrial matrix?

Answer 3

• The glycerol phosphate shuttle is bed to move reducing equivalents across the membrane
• Cytoplasmic NADH cannot cross the membrane but FADH can pass on its electrons on to the electron transport chain within the mitochondria

Question 4

How does the e’s of NADH get across the membrane of the mitochondria is it cannot cross the membrane?

Answer 4

Glycerol 3 Phosphate can cross the membrane and passes its electrons to FADH

Question 5

What is the generation of ATP of FADH compared to NADH?

Answer 5

• Less

- An energetic price is paid for using cytosolic reduced co-substrates in terminal respiration

Question 6

What is the name of complex I?

Answer 6

NADH-Q oxioredustase

Question 7

What is the name of complex II?

Answer 7

Sussinate - Q reductase

Question 8

What is the name of complex III?

Answer 8

Q Cytochrome C oxioreductase

Question 9

What happens at complex IV?

Answer 9

Cytochrome C oxidase

Question 10

What happens at complex I?

Answer 10

• NADH is oxidised and e’s are passed to ubiquinone to give uniquionol (QH2)
• H ions are pumped into the intramembrane space

Question 11

What happens at complex II?

Answer 11

FADH2 is oxidised and e’s are passed to ubiquinone to give ubiquinol

Question 12

What is uniquinone?

Answer 12

Dietary supplement believed to reduce free radicals and thus acts as an anti-oxidant

Question 13

What happens at complex III?

Answer 13

• Passes the e’s form ubiquional to cytochrome C
• 1 ubiquinol is oxidise to field 2 reduced cytochrome C molecules
• Pumps protons into the inter membrane space

Question 14

What happens at complex IV?

Answer 14

• Take e’s from cytochrome c and passes them to molecular O2 to form H2O
• e’s channelled through Fe-Cu centre
• Pumps protons into the inter membrane space

Question 15

What does the conservation of energy form the breakdown of food molecules ultimately lead to?

Answer 15

The oxidation of NADH, FADH2, ubiquinone and cytochrome C

Question 16

Hoe is energy further conserved?

Answer 16

By the setting up of proton gradient across the inner mitochondrial membrane

Question 17

How is the energy stored up in the H gradient used?

Answer 17

• The EMF acts as a proton motive force and allows the proton gradient to work
• A molecular turbine has beloved to harness the energy in the proton gradient - ATP synthase

Question 18

What is chemiosmosis?

Answer 18

As electron’s through the complexes of transport chain protons move from the matrix to the outside of the inner mitochondrial membrane

Question 19

Why is the movement of protons across the mitochondrial inner membrane classed as vectoral?

Answer 19

It has a particular spatial directionality