Respiration 4: mitochondrial pathology & ROS

Question 1

accumulation of pyruvate will lead to increased formation of what?

Answer 1

lactate

Question 2

accumulation of citrate will lead to increased formation of what?

Answer 2

fatty acids

Question 3

What complex and function does Cyanide affect?

Answer 3

complex 4; cyanide blocks the electron transfer to oxygen

Question 4

If electron transfer to oxygen in complex 4 is inhibited what happens?

Answer 4

ATP will not be synthesized because electron flow prior to complex 4 will be inhibited and so the proton gradient will diminish and ATP synthase will not work

Question 5

What does homoplasmy mean?

Answer 5

all of the copies of mitochondrial DNA in a particular cell are the same (all mutant or all wild type)

Question 6

What does heteroplasmy mean?

Answer 6

there are a mixture of mutant and wild type mitochondrial DNA

Question 7

which complex of the ETC is not encoded by mitochondrial DNA?

Answer 7

complex 2

Question 8

what happens to the chemiosmotic gradient if you take the diet pill DNP

Answer 8

the chemiosmotic gradient diminishes because the hydrogen ions leak back into the matrix not via ATP synthase

Question 9

what happens to the energy from electron transfer with mitochondrial uncoupling?

Answer 9

it is released as heat

Question 10

In which tissue is UCP1 most commonly found?

Answer 10

brown fat in bbs

Question 11

What is bad about ROS

Answer 11

ROS can damage lipids, proteins and DNA

Question 12

Where are ROS formed?

Answer 12

mitochondria

Question 13

what reaction does superoxide dismutase catalyze?

Answer 13

ROS –> hydrogen peroxide

Question 14

what reaction does catalase catalyze?

Answer 14

hydrogen peroxide –> H20