Exam 2: 14A (incomplete) Flashcards
What is chemiosmotic coupling?
Chemiosmotic coupling is the idea that the proton concentration gradient across the inner mitochondrial membrane, which is generated by the electron transport chain, is ultimately what drives ATP production via ATP synthase.
What drives ATP synthase?
The proton gradient between the intermembrane space and matrix in the mitochondria.
The electrochemical gradient in ETC:
High proton conc. in intermembrane space
Lower proton conc. in matrix
What makes up the phosphoanhydride bond of ATP?
ADP + Pi —> ATP
What generates the proton gradient in mitochondria?
The electron transport chain
How many protons does ATP synthase require to produce one ATP molecule?
3 H+ protons
(Proton translocation causes a rotation of the F0 subunit and the central shaft γ. Translocation of three protons fuels synthesis of one ATP.)
What organelle converts food into chemical energy known as ATP?
Mitochondria are the organelles that function as the powerhouse of the cell. They convert the chemical energy from the food into an energy in the form of ATP in which the cells can use in order to do its work.
What is the anatomy of the mitochondra?
Outer membrane: seperating intermembrane space and cytosol
Inner membrane: separating inter-membrane space and matrix
Cristae: invaginations of inner mitochondrial membrane
Mitochondria have to capacity to divide and fuse.
True
False
True, this is called fission.
(Mitochondria are dynamic organelles with the ability to fuse and divide (fission), forming constantly changing tubular networks in most eukaryotic cells. These mitochondrial dynamics, first observed over a hundred years ago are important for the health of the cell, and defects in dynamics lead to genetic disorders.)
How do mitochondrion travel?
along microtuble tracks,
(to increase efficiency mitochondria can move about to where it is most needed in the cell.)
Do mitochondria move unidirectionally or bidirectionally?
Among all the transported cargoes that had been described in the past, the mitochondrion appears to be the most frequently reported organelle that can be unidirectionally or bidirectionally transferred
Mitochondria interacts with late endosomes.
True
False
True, it is speculated that mitochondria and late endosomes interact to exchange lipids
Explain mitochondria’s movement in neurons.
Mitochondria is dynamic, and can move both directs on neuronal processesies
What determines a mitochondria’s ability to move long distances like in neurons.
Mitochondria can move long distances in highly polarized cells, like neurons.
Where can mitochondria be observed in fixed points of high energy demand?
skeletal or cardiac muscle cells (packed between myofibrils)
sperm cells (wrapped tightly around flagellum)
What is the highly dynamic relationship between mitochondria and the endoplasmic reticulum?
facilitation of lipids, and calcium exchange between membrane systems.
(occurs at sites of mitochondrial fission)
