Mitochondria Flashcards
Function of mitochondria
- Biosynthetic pathways (aa; nucleotides, porphyrins; cholesterol, nitricoxide, glutathione)
- Bioenergetic pathways ( aerobic oxidation of glucose; beta-oxidation of fatty acids)
- Anti-oxidant defence
- Redox status (NADH/NAD levels)
- Cell Signaling (ROS; Ca2+)
Compartment of Mitochondria
Outer membrane
Inter membrane space
Inner membrane
Matrix
Outer membran
Contain large channels forming proteins (porin)
Inter membrane space
Contain several enzymes that use the ATP passing out of the matrix to phosphorylate other nucleotide
Proteins released during apoptosis
Inner membran
Folder into numerous crises
Contain proteins that carry out oxidative phosphorylation
Including the ETS and ATP synthase Enzym
Matrix
High concentration of mixtures of hundreds of enzymes including for oxidation
Special features of Mitochondria
Can change their shape, location and number to suit a cells needs
Can divide like a bacterium (fission)
The origins of Mitochondrial RNA and proteins
They produce their own proteins because they have their own DNA
Mitochondria Import most of their lipids, but converts some imported lipids to cardiolipin (four fatty acids)
Transport of proteins into mitochondria
Through transmembrane transport
The protein which would go in the mitochondria must take signal sequence to bind to the import receptor which open the channel
Then bind to the protein translocator and get in the matrix- signal secuence cut away and the protein became a conformation (mature)
How obtain cells their energy
Cells obtain most of their energy by a membrane-based mechanisms that use the energy provided by food or sunshine to generate ATP
- from food=oxidative fosforilation
- from light=Fotosynthese
Membrane based systems use the energy stored in an electrochemical proton gradient to synthesis ATP
Sugar and fats
Both are degraded to Acetyl-CoA in Mitochondria
Produce after the acetyl coa cycle NADH and FADH which go to ETS and used for ATP
aTP synthase
The movement of electrons is coupled to the pumping of protons across the inner mitochondrial membrane
Activated carriers generated during the citric acid cycle power the production of ATP
Mitochondria catalyze a major conversion of energy
NADH transfers its electrons to oxygen through three large respiratory enzyme complex
The proton gradient then drives ATP synthesis
Quinones
Carry electrons within the lipid bilayer
The evolution of energy generating system
First the cells make fermentation because their was no o2
- To make ph basic they hidroliz ATP
- Can move H away and don’t use energy
- Now they can control both
Some major events are believed to have occurred during the evolution of living organisms on earth. Oxygen entered earth atmosphere billions of years ago
The genetic system of Mitochondria
Mitochondria contain complete genetic systems
The organization of human mitochondrial genome shows that animal mitochondria contain the simplest genetic system known
mtDNA can be homoplasmic(one Typ mtDNA cells) or heteroplasmic (Mutant and normal mtDNA together in one cell - in some diseases the mutant one growth)