Aerobic respiration Flashcards
Where does the kreb cycle occur?
Mitochondrial matrix
what are the two components of the aerobic system?>
krebs and electron transport chain
Where does the Electron transport chain occur?
Inner mitochondrial membrane
What are the products of oxidative phosphorylation?
water and ATP
Amount of carbs stored in the body?
300-400g
Carbs stored in the liver?
70-100g stored in the liver
oxidation
is the addition of oxygen, removal of hydrogen, or the removal of electrons from an element or compound
what is reduction?
the deletion of oxygen, addition of hydrogen, or addition of electrons to an element or compound
where is the location of Aerobic respiration?
Mitochondria
Products of Aerobic respiration?
ATP, NADH, FADH2
key enzymes in aerobic respiration?
dehydrogenase
What are the names for krebs cycle?
citric acid cycle, TCA (tricarboxylic acid cycle)
Where do NADH and FADH2 deliver their electrons to?
Electron Transport chain
When do Carbs enter the krebs cycle?
enter after running through glycolysis and a prep step
Acetyl -CoA
What does Coenzyme A consist of?
pantothenic acid (b5) and a terminal thiol (SH) group
what does acyl Coa dehydrogenase do?
oxidizes Acetyl CoA
What is the multi-enzyme complex that is also irreversible in the krebs cycle?
pyruvate dehydrogenase
How is the outer membrane of the mitochondria?
porous
permeable to most ons and small molecules
How’s the inner membrane of mitochondrial membrane?
convoluted,
impermeable to most small ios and small molecules…
what are the final products of aerobic metabolism?
CO2, H2O, ATP
What reduces NAD+?
dehydrogenase
What is complex 1?
NADH dehydrogenase
What is complex 2?
succinate dehydrogenase
what is complex 3?
cytochrome reductase (bc1)
What is complex 4?
cytochrome oxidase ()
What part of complex 1 accepts the electrons from NADH?
FMN (Flavin mononucleotide)
What molecule is bound to complex 1?
Flavin mononucleotide (FMN)
Where does complex 1 transfer electrons to ?
ubiquinone (CoQ)
Does complex 1 participate in the proton pump?
yes
What does complex 2 do?
oxidizes succinate
gives electrons to FAD to FADH2
Is any energy lost in complex 2?
no, no proton pump at this complex
is ubiquinone a protein?
no
From where does ubquinone accept electrons?
FADH2 or FMNH2
Where do FADH2 come from to ubiquinone?
succinate dehydrogenase
2.
3.
Which complexes contain a heme group?
complex 3 and 4
How do electrons flow from complex 3?
complex 3 to cytocrhome c to complex 4
which complex is the bimetallic center?
complex 4 (AKA cytochrome c oxidase or cytochrome a +a3)
what does the bimetallic center of complex 4 contain?
cytochromes a and a3 have iron atoms
two copper ions
Which complex does NOT pump protons to the intermembrane space?
complex 2
What compounds are oxidized within the aerobic system?
Fat
carbohydrate
protein
Where is the prep step for aerobic respiration?
mitohondrial matrix
products of Aerobic respiration?
ATP, NADH, FADH2
What compounds does Krebs cycle take in?
fat, CHO, proteins
How do carbs enter the Krebs cycle?
Enter after running through glycolysis and a prep step (Acetyl CoA)
How do Fats enter the Krebs cycle?
Enter after running through Beta oxidation.
Acetyl CoA
How do proteins enter the Krebs cycle?
Each AA is unique in how it enters.
Acetyl CoA + other intermediates
Not all tissue can oxidize all AA
What is the universal carrier of acyl groups?
Coenzyme A
When is coenzyme A used?
used in fatty acid synthesis and oxidation, pyruvate oxidation and acetylation
what kinds of bonds does Coenzyme A consist of?
forms high-energy thioester bonds with acetic acid (acetyl CoA) and fatty acids (acyl CoA)
what is the main enzyme in fatty acid entry into the krebs cycle?
Acyl CoA dehydrogenase
Where does Fatty acid entry occur?
mitochondrial matrix
What is the oxidation of fatty acid?
where a two carbon molecule (acetyl CoA) is cleaved off the fatty acid
what are the intermediates for Amino acids other than Acetyl CoA?
alpha-ketoglutarate
succinyl CoA
Fumarate
Oxaloacetate
What are the 3 enzymes that make up the pyruvate dehydrogenase complex?
E1. Pyruvate dehydrogenase (AKA: pyruvate carboxylase)
E2: Dihydrolipoamide acetyltransferase
E3: dihydrolipoamide dehydrogenase
What are the 5 co-enzymes in pyruvate dehydrogenase complex?
- Thiamine pyrophosphate (TPP)
- Flavin adenine dinucleotide (FAD)
- Nicotinamide adenine dinucleotide (NAD)
- Coenzyme A
- Lipoate
What are the products of the krebs cycle that inhibit it?
ATP
High Energy Charge
NADH
FADH2
What are the reactants that stimulate the Krebs cycle?
ADP or AMP
Low energy charge
NAD+
FAD
What are the main enzymes in the krebs cycle?
Isocitrate dehydrogenase
alpha-ketoglutarate dehydrogenase
Succinate dehydrogenase
Malate dehydrogenase
What is an example of a product inhibiting its enzyme?
Succinyl CoA (there are many more)
alpha-ketoglutarate dehydrogenase complex is regulated by energy charge and inhibited by?
ATP
NADH
Succinyl CoA
What two components regulate isocitrate dehydrogense?
Regulated by Energy (ATP/ADP) and Redox state (NADH/NAD+)
What inhibits isocitrate dehydrogenase?
It’s products: ATP and NADH
What stimulates Isocitrate dehydrogenase?
it’s reactants: NAD+ and ADP
What inhibits Citrate synthase?
High products: ATP/citrate
Low reactants: Oxaloacetate and/or acetyl CoA
What inhibit pyruvate dehydrogenase?
high NADH/NAD+
High Acetyl CoA/CoA
High ATP/ADP
availability of long-chain fatty acids
What is anaplerotic?
giving substrates to the cycle
what is cataplerotic
taking substrates from the cycle
what are the intermediates the leave the krebs cycle to make amino acids and nucleotides?
oxaloacetate and alpha-ketoglutarate
where is oxaloacetate sent to make glucose?
gluconeogenesis
In the aerobic cycle what is the ultimate acceptor of the electrons?
oxygen
How do you convert GTP to ATP?
(GTP + ADP) –nulceoside dihophokinase–> (GDP + ATP)
How do we yield GTP from the krebs cycle?
cleaving the thioester bond of Succinyl CoA release energy and the formation of GTP is coupled to this reasion.
by which point have molecules lost 3 Carbons to CO2?
decarboxylaions
1 to prep step, 2 lost in krebs cycle
what is cytochrome c?
a small protein (FeS complexes) in the ETC
What does cytochrome c do?
transfers electrons to cytochrome oxidase
location of cytochrome c?
intermembrane space
How many electrons are required to reduce 1 molecule of O2 to H2O?
4e’s
What is the chemiosmotic theory?
(a theory that states) When protons flow through a special protein, ATP is created.
In ATP synthase (complex 5) what gives the energy to create atp?
the return flow of protons gives the energy needed for ATP synthesis
What is respiratory control dependent on?
the ability to phosphorylate (ADP to ATP)
What does Oligomcin prevent?
ATP synthesis
what does 2,4-dinitrophenol do?
diffuses easily through inner mitochondrial membrane and stopped ATP production. Increases ETS rate, but no proton gradient (NO ATP production)
How do the flows of electrons go?
electrons flow from the more negative E0 redox pair to the more positive E0 redox pair
