mitochondria: energy Flashcards
describe the structure of a mitochrondrai
high specialised with an outer an inner membrane
inner one is hihgly folded
whats special about the inner membrane
full of cardiolipin which makes the membrane impereable to ions
this is a hihgly specialsed lipid bilayer
what does the mitochondria matrix contain
enzymes that metabolise pyruvate and fatty acids to produce acetyl CoA and enzymes that oxidise citric acid cycle
what is reduction andd oxidation
reduction is adding/gain
oxidation is removing/loss
how is FAD reduced?
addition of 2 electrons and protons
what is oxidative photphylation
glucose can be metabolised through oxidation to produce energy in glycolysis
where does oxidative phosophylation in glycolysis happen>
in the cytosol
glucose is broken down to produce energy as ATP
how many atp can one molecule of glucose produce
2ATP
where does the citric acid cycle occur?
in the matrix
what does the citric acid cycle produce
electron carriers such as NADH for electron transport chain
building blocks for cells and ATP
what are fed into the citric acid cycle?
fatty acids, amino acids, sugars
what are transfered to the electron transport chain?
NADH and FADH
how are electrons passed in the transport chain to fnally oxygen>
passed through number of prteins including cytochromes wth an iron atom to finally reach oxygen
what does the electron chain function to do?
break the large free-energy drop from food to oxygen into smaller steps that release manageable energy in smaller bits
what helps transfere the electrons from NADH to oxygen exactly?
large respiratory enzyme complexes located in the inner membrane of the mitochondria
work through a series of alternate reduction and oxidation steps
where does the electron transport chain occur
in the cristae
desribe the process of the electron in the chain
- NADH passes electron to first part of the chain
- NADH dehydrogenase is first complex ]
- NADH oxidised to NAD+
- complex reduced now
- now electron passed to ubiquinone Q
- quinnone reduced and is oxidised
- cycle to redox reactions
- passed onto cytochrome BC1
- passed onto final cytochrome oxidase
name the enzyme cpmplexes in the electron chain
NADH dehydogenase ( large complex) ubiquinone Q cytochrome BC1 ( large complex) cytochome C cytochrome oxidase ( Large complex)
what us the importance of oxygen?
this is what 90% of the oxygen we breath in used for, final electron acceptor
why is cytochrome C important
key for cell death as well as electron transport energy production
what does cyanide do to the body?
toxic as it binds to cytochrom oxidase complex, stopping electron transport and reducing ATP production
name some carriers of electrons only
FeS iron sulphur proteins
cytochromes
nanme some carriers of electrons and H+ ions
FMN: flavin mononucleotide
FAD
uniquinnone Q
oxygen
where are protons moved to in the electrons transport chain?
moved into the intermembrane space out of the matrix creating a gradient
why cant the protons move back across the membranes in electron transport?
the inner membrane is impermeable to ions
they et stuck on the other side creating the gradient
what is the final component of electron transport chain??
ATP synthase
what is ATP synthase
channel that carries protons
moving the protons through here synthesies ATP
the force of the protons drives the production of ATP
describe the structure of ATP synthase
little channels on the top
protons flow into channels and out the other side
protosn twist the molecule, this mechanical twisting makes the ATP
what is ATP synthase an example of?
chemiosmosis
describe the process of chemiosmoso
the enery coupling mechanism
proteins pump hydrogen ions from mitochondria matrix to intermembrane space
H ions then move back across through ATP synthase
drives ADP into ATP
* use of enery is a H+ gradient to drive cellular work
which part of respiration makes the most ATP
electron transport chain: 38 molecules from one molecule of glucose
what is mitochondria uncoupling?
controlling the efficiency of the process
what happens in mitochondria uncoupling
break the cycle
instead of pumping protons to synthase, the membrane is made leaky and protons can flow out losing energy as heat
what is used in mitochondrial uncoupling to make the membrane leaky?
DNP
what is uncoupling proteins UCPs
mitochondria transporter present in the inner membrane
found in mammals and plants
what does as UCP allow
continuous rexoidation of coenzymes that are essential to metabolic pathways
what is the function of a UCP (uncoupling proteins)
help make more heat
retain temperture
is the body priority is heat generation, what happens to repiration?
this becaome uncoupled and there is ots of heat generaton
is the bodys priotiry is heat generation what happens
the mitochondra becomes leaky and heat is lost
is the bodys priority is energy conservation what happens?
respiration is well-coupled and the protons are not leaky
in cold places what do you do to respiartion?
uncouple to make more heat
how is ATP synthesised in bacteria
respiration:
pump the protons outwards allowing them to re-enter via ATP synthase
what is the evidence for ATP snthesis in bacteria
the make it the same as we do in mitochdonria
explains endosymbiosis
