L29- Mitochondrial Structure and Citric Acid Cycle Flashcards
Briefly describe the structure of the mitochondria.
its made from 2 layers inner and outer membranes and intermembrane space in between and matrix space enclosed by the inner membrane
describe the outer membrane of the mitochondria.
it freely permeable to large molecules because it contains many porins and contains additional proteins that make the mitochondrial lipids
describe the inner membrane of the mitochondria
its folded into cristae to provide large surface are for the production of ATP.
ATP synthase is a structure present on the inner membrane and its responsible for the formation of ATP
state the content of the matrix of the mitochondria
1- soluble and insoluble proteins
2- tuna mana and ribosomes
3-cDNA
4-enzymes necessary for expression of mitochondrial DNA
state the 4 characteristics of the mitochondria
1- they are self-replicating
2- they can increase cristae increase in size or fuse together to form large mitochondria (hypertrophy) in response to hyperactivity
3- undergo fusion to increase their number (hyperplasia).
4- can replicate their DNA
what is the citric acid cycle?
its the final common pathway for complete oxidation of carbohydrates fatty acids and many amino acids. its an aerobic process occurring inside the mitochondria.
explain the importance of the citric acid cycle
1) energy production: 12ATP molecules 3 from NADH 1 from FADH2 and ! from GTP
2 )final common pathway for complete oxidation of carbohydrates fatty acids and many amino acids as they all provide acetyl CoA.
3) it produces intermediates used in the synthesis of cholesterol nonessential amino acids and fatty acids
4) carbon dioxide produces is used in many important reactions including different co2 fixation reactions, purines and pyrimidines
name the 3 key regulatory enzymes of the citric acid cycle.
CITRATE SYNTHASE, ISOCITRATE DEHYDROGENASE, ALPHA KETOGLUTARATE DEHYDROGENASE.
What happens when ATP levels are high?
ATP inhibits both citrate synthase and isocitrate dehydrogenase which are both activated buy high levels of ADP
what inhibits the Citric acid cycle?
high levels of ATP and NADH because energy is already available no need to produce more.
what happened during high levels of NADH?
it inhibits both isocitrate dehydrogenase and alpha ketoglutarate dehydrogenase.
effect of high level of acetyl coA and oxaloacetate on can
ACTIVATE CITRATE SYNTHESASE
effect of high level of succinylcholine coA
inhibit alpha ketoglutarate dehydrogenase
