Outline the main features of the mitochondria.
Matrix- contains DNA, ribosomes and enzymes
Inner membrane- folded into numerous cristae, contains transport proteins and protein complexes
Outer membrane- contains channel proteins-porins
Inter membrane space- contains proteins and enzymes
Outline the major contributions of the mitochondria, in addition to energy production.
Buffering redox potential in the cytosol
Membrane growth- uses citrates (used to make fatty acids) from TCA cycle
Urea cycle- detoxifies ammonia
Biosynthesis of haven groups
Produces ROS (reactive oxygen species) due to leaky membrane. These are used as signal molecules that activate transcription factors
Localised mitochondrial functions: inner membrane
Electron transport
Oxidative phosphorylation
Pyruvate transport
Fatty acyl CoA import
Metabolite transport
Localised mitochondrial functions: outer membrane
Phospholipid synthesis
Fatty acid desaturation
Fatty acid elongation
Localised mitochondrial functions: matrix
Pyruavte oxidation
Citric acid cycle
Beta oxidation of fats
DNA replication
RNA synthesis
Protein sysnthesis
What is a catabolic pathway?
release energy by breaking down complex molecules (macromolecules) into simpler compounds
Synthesis < consumption
Describe anabolic pathways.
consume energy to build complex molecules from simpler ones
Synthesis > consumption
Describe the process of glycolysis.
Glucose is converted into glucose-6-phosphate, reaction is catalysed by the enzyme hexokinase and energy from ATP hydrolysis is used
G-6-P is isomerise by isomerise into fructose-6-phosphate
F-6-P converted into fructose 1-6-biphosphaye , energy from ATP hydrolysis is used and catalysed by enzyme aldolase
Glyceraldehyde 3 phosphate is produced
A series of reactions catalysed by enzymes produces 2 molecules of pyruvate from 1 molecule of glucose
Pyruvate enters mitochondrial matrix via channel protein and is decarboxylated and oxidised forming acetate and CO2
Acetate combines with co-enzyme A to form acetyl-CoA
2 ATP is used and 4 produced= net yield of 2 ATP and 4 NADH produced
Describe the process of citric cycle
Acetyl-CoA (2C) combines with oxaloacetate (4C) catalysed by enzyme citrate synthese to form citrate (6C) (used to make fatty acids)
Citrate isomerise by enzyme aconitine into isocitrate
Isocitrate oxidised to alpha ketoglutarate (5C) by enzyme isocitrate dehydrogenase releasing CO2 and reducing NAD into NADH
Alpha-ketoglutarate (5C) can be converted into glutamate (amino acid)
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