citric acid cycle

Question 1

glycolysis process

Answer 1

glucose –> 2pyruvate

Question 2

lactate is a product of

Answer 2

aerobic respiration

Question 3

the citric acid cycle occurs during

Answer 3

aerobic respiration and is responsible for the generation of ATP and NADH and FADH

Question 4

citric acid cycle is also known

Answer 4

kreb or TCA cycle tricarboxylic acid

Question 5

the citric acid produces ….e- for oxidative phosphorylation

Answer 5

8 electrons -used to pump 36H+ across the mitochondrial inner membrane into the mitochondria space –> produces 9atp via ATP synthase

Question 6

the citric acid cycle is an important course of precursors

Answer 6

-storage form of rules -bulding blocks of amino acids -building blocks of nucleotide bases -cholesterol, heme

Question 7

occurs in the

Answer 7

mitochondrial matrix

Question 8

purpose of TCA

Answer 8

to harvest high energy electrons from carbon rules and generate NADH and FADH2

Question 9

what are the 2 carbon units that arrive to be oxidised

Answer 9

acetyl CoA

Question 10

mitochondria

Answer 10

..

Question 11

formation of Acetyl CoA

Answer 11

pyruvate +CoA +NAD+ –> acetyl CoA + CO2 +NADH

Question 12

by product of the link reaction

Answer 12

carbon dioxide

Question 13

which enzyme catalyses pyruvate to acetyl co A

Answer 13

pyruvate dehydrogenase complex

Question 14

a specific carrier transports oyrivate into the

Answer 14

mitochondria from the cytoplasm (where glycolysis occurs)

Question 15

during the link reaction pyruvate is

Answer 15

oxidatively decarboxylated t acetyl CoA -by pyruvate dehydoregnase

Question 16

the link reaction is..

Answer 16

irreversible -loss of carbon is irreversible

Question 17

pyruvate dehydrogenase

Answer 17

multi-enzyme complex giant -4-10 million daltons -can be seen using an electron microscope

Question 18

chemical link reaction via pyruvate (pic)

Answer 18

• first pyruvate is decarboxylates and CO2 is released. then the complex is oxidised and loses 2 e-. Now the complex carries a positive charge and this means that CoA can be transferred –> acetyl CoA

Question 19

pic of the citric acid cycle

Answer 19

pic

Question 20

order of the citric acid cycle starting from when acetyl CoA joins oxaloacetate clare is knitting saskia some fleeces mostly orange

Answer 20

citrate isocitrare ketoglutarate succinyl CoA succinate Fumarate malate oxaloacetate

Question 21

order of citric acid cycle

Answer 21

citrate isocitrate ketogluatarge succinyl coA succinate fumarate malate oxaloacetate

Question 22

Oxaloacetate + acetyl CoA

Answer 22

-citrate synthase -adol condensation reaction followed by hydrolysis -citrylCoA and citrate

Question 23

adol condensation reaction followed by hydrolysis with citrate synthase

Answer 23

ocaloacetate + acetyl CoA –> Citryl CoA + citrate

Question 24

citrate loses water to form

Answer 24

cis-aconitate (intermediate) gains water to form isocitrate -both step of the reaction are catalysed by ACONITASE

Question 25

aconitase

Answer 25

-an iron-sulfur protein -one of the iron atoms binds to the citrate -the iron facilitates the dehydration/hydration reactions

Question 26

isocitrate --\> NAD+ is reduced to form a NADH +H+

Answer 26

produces oxalosuccinate, then it is protonated and CO2 is lost producing ketoglutarate -isocitrate dehydrogenase

Question 27

alpha ketoglutarate

Answer 27

key step in the production of nADH NAD+ and CoA joins ketoglutarate and Succinyl CoA is formed as well as CO2 and NADH

Question 28

succinyl CoA joins with

Answer 28

Pi and GDP to form Succinate and CoA + GTP succinyl CoA synthetase

Question 29

Succinate to fumarate

Answer 29

succinate dehydrogenase -key step in production of FADH

Question 30

Fumarate to malate

Answer 30

fumarase

Question 31

malate to oxaloacetate

Answer 31

malate dehydrogenase -key step in production of nADH

Question 32

how is TCA regulated

Answer 32

concentration fo ATP and NADH

Question 33

key control points are

Answer 33

-isocitrate dehydrogenase -alpha ketoglutatrta dehydrogenase

Question 34

other control points

Answer 34

-pyruvate dehydrogenase irreversible loss of C) -isocitatrate dehydrogenase- inhibited by ATP and NADH -Ketoglutarate dehydrogenase- inhabited by ATP, succinyl CoA and NADH

Question 35

isocitrate dehydrogenase

Answer 35

inhibited by ATP and NADH

Question 36

ketoglutarate dehydrogenase

Answer 36

inhabited by ATP, succinyl CoA and nADH

Question 37

overall picture of the citric acid cycle

Answer 37

Acetyl CoA + 3NAD+ + FAD +GDP +Pi --\> 2CO2 + 3NADH + FADH2 + GTP +CoA

Question 38

during the citric acid cycle there is still not a lot of

Answer 38

ATP or GTP generated

Question 39

product yields

Answer 39

2 molecules of CO2 GTP 3NADH (6 electrons) FADH (2 electrons)

Question 40

3NADH

Answer 40

6 electrons

Question 41

FADH

Answer 41

2 electrons

Question 42

summary of TCA

Answer 42

-generates NADH and FADH2 -utilised by ETC -together, the citric acid cycle and the electrons transport chain provides \>95% of the energy used by aerobic cells -also generates vital metabolic precursors

Question 43

pathways linked to the citric acid cycle

Answer 43

pic

Question 44

arsenic inhibits the Citric acid cycle

Answer 44

arsenic and mercury inbits pyrvate dehydrogenase complex by inactivating the dihydrolipomide component of the transacetylase -leads to central nervous system pathologies

Question 45

which enzyme is inhabited by arsenic and mercury

Answer 45

inhibits pyruvate dehydrogenase complex by inactivating the dihydrolipomide component of the transacetylase.

Question 46

mad as a hatter

Answer 46

the strange behaviour of hat makers who sued mercury nitrate

Question 47

lewisite

Answer 47

arsenic based chemical weapon in WW2 BAL (british anti-lewisite) was used as an antidote