Mitochondria Flashcards
Where are mitochondria mostly clustered?
in regions of greatest metabolic activity (greatest need of ATP)
what is the name of the theory that says mitochondria are descended from ancient bacteria, which were engulfed by the ancestors of eukaryotic cells more than a billion years ago
Endosymbiotic theory
what are the beta barrel shaped integral proteins on the outer membrane of the mitochondria called?
porins
what is the maximum size of molecules that can pass through porins?
<5000 Daltons
Where in the mitochondria is cytochrome c found?
inter membrane space
which area of the mitochondria has the same concentrations of ions and sugars as cytosol?
inter membrane space
what does ATP synthase do?
generates the energy storage molecule ATP from ADP and inorganic phosphate
what are the folds in the matrix of the mitochondria called?
cristae
what are the four functions of the inner membrane proteins
- Oxidative phosphorylation
- ATP synthesis
- transport proteins
- Protein import machinery
which mitochondrial membrane is highly impermeable to all molecules?
the inner membrane due to it not containing porins
What is ATP Synthase?
An enzyme that synthesises ATP from ADP and inorganic phosphate (Pi)
Which membrane has a high protein to phospholipid ratio
the inner membrane (More than 3:1 by weight (1protein for 15phospholipids)
why is cardiolipin so unusual?
it contains four fatty acids rather than two and may help to make the inner membrane impermeable
which membrane requires almost all ions and molecules to be transported by transport proteins to enter or exit the matrix
the inner membrane
which membrane is rich in cardiolipin
the inner membrane
what is the function of cristae
they expand the inner mitochondrial membrane space creating more surface area which enhances its ability to produce ATP
why does muscle cell mitochondria contain more cristae than typical liver cell mitochondria?
greater demand for ATP
which part of the mitochondria contains about 2/3 of the total protein found in a mitochondrion ?
the matrix
which site is important in the production of ATP with the aid of ATP synthase (contained in the inner membrane)
the matrix
Where in the mitochondrion can a highly concentrated mixture of 100s of enzymes be found?
the matrix
which mitochondrial membrane is responsible for phospholipid synthesis?
outer membrane
which mitochondrial membrane is responsible for fatty acid desaturation?
outer membrane
which mitochondrial membrane is responsible for electron transport chain redox reactions?
inner membrane
which mitochondrial membrane is responsible for pyruvate oxidation?
matrix
which mitochondrial membrane is responsible for oxidative phosphorylation?
inner membrane
which mitochondrial membrane is responsible for fatty acid elongation?
outer membrane
which mitochondrial membrane is responsible for the TCA (krebs) cycle
matrix
which mitochondrial membrane is responsible for pyruvate import
inner membrane
which mitochondrial membrane is responsible for fatty acyl CoA import
inner membrane
which mitochondrial membrane is responsible for beta oxidation of fats
matrix
which mitochondrial membrane is responsible for metabolite transport
inner membrane
which mitochondrial membrane is responsible for DNA replication
matrix
which mitochondrial membrane is responsible for RNA synthesis (transcription)
matrix
which mitochondrial membrane is responsible for protein synthesis (translation)
matrix
What is produced when ADP is catalysed by ATP synthase and a phosphate group
ATP and H2O
Where is the concentration of H+ ions at its greatest within the mitochondria?
inner membrane
what produces the electrochemical force that turns the driveshaft subunit in ATP synthase?
Protons (H+)
The overall reaction catalyzed by ATP synthase is:
ADP + Pi + 3H+out ⇌ ATP + H2O + 3H+in
Which ATP synthase subunit is hydrophobic?
FO region
Which ATP synthase subunit region is hydrophilic
F1 region
ATP synthase uses a chemiosmotic proton gradient to power ATP synthesis through which chemical process?
oxidative phosphorylation
Which ATP synthase subunit protrudes into the mitochondrial matrix
F1 region
