Mitochondria A Flashcards
main energy source for cell
ATP, high energy bonds in ATP
adenosine- tri-phosphate
production of ATP is required for
cell to function
principal source of ATP in animals are ___ and ____
fatty acids
glucose
the initial stages of glucose degradation occur in the
cytosol
the terminal stages that involve oxygen occur in the _____ and are known as _____
mitochondria
oxidative phosphorylation
what is the power plant of the cell?
mitochondria
how did mitochondria evolve?
eukaryotic cells by endocytosis of bacteria that are capable of oxidaive phosphorylation
endosymbiont hypothesis means that the inner membrane of mitochondria is derived from _____, while the outer membrane is derived from ____
bacteria
eukaryotic cell
most cells contain mitochondria that can occupy up to _____% of cell volume
25
the outer membrane is _____
the inner membrane is _____
semi-permeable
much less permeable
which membrane contains most the the machinery for oxidative phosphorylation?
inner membrane
function of cristae?
Cristae are the infoldings in the inner membrane that greatly increase the surface area
Where is the mitochondrial matrix located?
the central space of the mitochondria
Mitochondria have their DNA located where?
in the matrix
A majority of mitochondrial proteins are encoded in nucleus, these proteins are synthesized in cytosol and imported via ____ and _____
TOM and TIM complexes.
TOM
tranlocase of outer membrane
TIM
translocase of the inner membrane
Transport through TOM is _____, while transport through TIM is _______.
passive
ATP-dependent
Most of the mitochondrial proteins are encoded where?
in the nucleus
The mitochondrial proteins are synthesized in the _____
cytosol
Mitochondria are very dynamic organelles that undergo constant _______.
fusion and fission
Fusion role?
plays a key role in repairing damaged mitochondria
Fission is required for ______.
mitophagy
Fusion and fission are both dependent on _____
cellular GTPases:
Mfn and OPA1 (fusion),
and
Fis1 and Drp (fission).
Most of the free energy released during oxidation of glucose is retained in the _______.
reducing coenzymes such as NADH (nicotinamide adenine dinucleotide)
During respiration in mitochondria, electrons are released from _____ and transferred to ____ to form ____.
NADH
O2
H2O
Electron transfer occurs across the _______ and is achieved by ______
inner membrane
four major protein complexes that are embedded in the inner mitochondria membrane.
What occurs during the electron transfer process?
protons from mitochondrial matrix are pumped across the inner membrane.
The electron transport generates a _______.
proton concentration gradient
Proton transport also generates an ______.
electric potential across the inner mitochondria membrane (more negative in matrix as compared to outside of mitochondria)
the energy released from NADH is stored both as an ________
electric potential and a proton concentration gradient in mitochondria.
The ________ is a major source of ATP (and energy) in animal cells.
ATP synthesis from ADP and Pi (inorganic phosphate) coupled to electron transfer from NADH
____ and ____ is directly used to make ATP.
Proton gradient and electric potential
