terminal respiration

Question 1

where does terminal respiration take place?

what does this mean for FADH2 and NADH.

Answer 1

in the mitochondrial matrix.
most FADH2 and NADH is already present in the mitochondria as a product of citric acid cycle and FA synthesis.
The NADH cannot be transported into the matrix but the FADH2 can. glycerol-3 phosphate can be used as an intermediate to transport it.
NADH- NAD+ + H+- DAP to glycerol-3-phosphate- FADH2- ETC

Question 2

The ETC complex

Answer 2

It is found in the inner membrane of the mitcohondria.
-Complex 1- NADH-Q oxidoreductase.
NADH releases electrons to ubiquinone to form ubiquinol QH2. It uses Fe-S centres. H+ releases into intermembranal space
-Complex-2 Succinate-Q reductase
FADH2 releases e’s to ubiquinone to form QH2. Uses Fe-S centres.
-Complex-3 Q-cytochrome C oxidoreductase
QH2 releases electrons to cytochrome C ( forms 2)
H+ pumped into intermembranal space
-Complex 4: cytochrome C oxidase
Takes e’s from cytochrome C and passes them onto 02
uses Fe-S centres
Pumps H+ into the intermembranal space.

Question 3

ATP synthase

Answer 3

Occurs at ATP synthase- complex molecule which is made up pf F0- connects the molecule to the membrane and F1- protrudes into mitochondrial matrix.
When H+ flow in from the +ve side to the -ve side of the membrane. ADP and Pi bind to enter subunit-B in F1. F0 turns and this causes a conformational change which causes ATP to be produced.

Question 4

how much ATP is produced?

Answer 4

1 mole of ATP produced on average for every 3 H+ produced.
On average for 1 NADH, 8 H+ pumped into intermembranal space.
1 FADH2 enters at complex 2 so fewer H+ pumped out so less ATP produced.
on average, 2.5 per NADH and 1.5 per FADH2

Question 5

What would happen if the membrane became permeable to H+?

Answer 5

No concentration gradient. 
ATP ase not activated
02 reduced to H20
e's released as heat rather than ATP
ETC still takes place

Question 6

Intentional coupling in babies

Answer 6

Thermogenin- sits on the inner membrane of the mitochondrial membrane of brown fat cells
When the baby gets cold -epinephrine is released and causes opening of thermogenin

Question 7

Malignant hyperthermia

Answer 7

Leaky muscle channels which uncouple the electron transfer chain and ATP synthase