The Citric Acid Cycle and Terminal Respiration

Question 1

where does citric acid cycle occur

Answer 1

mitochondrial matrix

Question 2

where do electrons go after the CAC

Answer 2

passes them on to form NADH and FADH2

Question 3

what is oxidization

Answer 3

the loss of electrons

Question 4

where does Acetyl CoA come from

Answer 4

pyruvate from glycolysis and fatty acids are oxidized further to produce Acetyl CoA

Question 5

how many molecules of ATP comes from one molecule of glucose

Answer 5

2

Question 6

why is it dangerous for too much oxygen molecules

Answer 6

free radicals forming

Question 7

electrons from the citric acid cycle (and before) binds with electron carriers to ultimately produce what

Answer 7

water

Question 8

what do the electrons from the citric acid cycle (and before) combine with to produce water

Answer 8

protons and molecular oxygen

Question 9

in simple terms, what does the acid citric cycle do

Answer 9

to harvest electrons to oxidise food molecules to CO2 and H2O

Question 10

how is pyruvate dehydrogenase regulated

Answer 10

by its intermediate products and ATP (from the end point of cellular respiration)

Question 11

if the cell has enough energy, what molecules regulate the pyruvate dehydrogenase complex

Answer 11

ATP, Acetyl CoA and NADH

Question 12

if the cell needs more energy, what molecules regulate the pyruvate dehydrogenase complex

Answer 12

pyruvate and ADP

Question 13

blocking isocitrate dehydrogenase causs what

Answer 13

citrate build up

Question 14

what are the consequences of citrate build up

Answer 14

citrate will shuttle into the cytoplasm causing PFK1 to stop glycolysis

Question 15

what can activate pyruvate carboxylase

Answer 15

the build up of acetyl CoA

Question 16

what does anaplerotic mean

Answer 16

Greek work meaning to fill up

Question 17

where is the only site of oxidative phosphorylation in eukaryotes

Answer 17

mitochondria specifically in the mitochondrial matrix

Question 18

where does beta-oxidation happen in the cell

Answer 18

mitochondrial matrix

Question 19

what does oxidoreductase do

Answer 19

oxidises one thing while reducing some thing else

Question 20

what is in the middle of a oxidoreductase complex

Answer 20

iron-sulfur centres

Question 21

what is the purpose of iron-sulfur centres

Answer 21

to allow electrons to pass through the (oxidoreductase) complex and eventually passing the electrons to ubiquinone (Q)

Question 22

what does the heme group do in complex 2 in the electron transport chain

Answer 22

it blocks stray e-‘s that are coming up from the iron-sulfur centres

Question 23

if the heme group in complex 2 is deformed, what can happen?

Answer 23

electrons can start forming free radicals of O2 (superoxide) - leading to paraganglioma (in some tissues)

Question 24

what is paraganglioma

Answer 24

benign tumours in the head and neck - particularly in the carotid body

Question 25

how many reduced cytochrome c is made from oxidising one ubiquinol

Answer 25

2

Question 26

in complex 4 in the electron transport chain, how do electrons pass through

Answer 26

they go through iron-copper centres

Question 27

hoe do the energy stored up in the H+ gradient used

Answer 27

proton motive work (the chemical charges on either side of the membrane and pH differences) AND molecular turbine

Question 28

what is chemiosmosis

Answer 28

the movement of protons from the one side of a membrane to the other

Question 29

ATPase described in detail

Answer 29

two parts: F0 and F1, F0 rotates, F1 had 6 sub units (3 alpha and 3 beta), gamma subunit on the middle (where electrons pass through to bind with ADP and Pi

Question 30

what subunit does the ADP and Pi enter in the ATPase

Answer 30

beta subunit

Question 31

why does F0 rotate in ATPase

Answer 31

to separate the ATP from the beta subunit

Question 32

what is malignant hyperthermia

Answer 32

diseased caused by leaky mitochondrial membranes that uncouple electron transport and ATPase

Question 33

what does halothane do

Answer 33

it causes leaky inner mitochondrial membranes in muscle leaky in some way

Question 34

intentional uncoupling of ATPase and …, what happens

Answer 34

nor-epinephrine triggers the opening of a channel in a protein called thermogenin. Breaks the gradient and protons come in and out of the matrix. the energy that would have been stored is released as heat