Glycolysis Flashcards
(12 cards)
What are the two irreversible steps of glycolysis?
1 and 3
What is the committing step of glycolysis?
3
What enzyme catalyses the rate committing step of glycolysis and what regulates this?
phosphofructokinase (PFK) and high atp inhibits this reaction whereas high amp stimulates it.
What is the enzyme that catalyses the first, irreversible step of glycolysis p?
Hexokinase (or glucokinase when there is a large amount of glucose)
Why is the addition of the phsophyrl group to sugars important?
Makes the sugar anionic (with a negative charge) which prevents the sugar crossing the plasma membrane.
What are the features of glycogen as a storage molecule?
Has alpha 1,4 and alpha 1,6 glycosidic bonds in a 1:10 ratio, is highly branched and found in granules in the liver and skeletal muscle.m
What are the features of the storage molecule cellulose?
Contains beta 1,4 glycosidic linkages, which the gastrointestinal tract does not produce enzymes to hydrolyse.
What other substrate does reaction 6 of glycolysis require?
NAD+
What molecules is reproduced by the reaction of pyruvate to produce lactate?
NAD+
What factors can lead to the increased production of lactate?
Increased production in congestive heart disease, shock, healthy eating and strenuous exercise and decreased utilisation in liver disease, thiamine deficiency and during alcohol metabolism.
What is lactic acidosis?
When plasma lactate rises above 5mmol/l, which is above the renal threshold of the kidney and begins to affect the buffering capacity of blood.
What are the products of glycolysis?
2ATP, 2NADH and 2 pyruvate.
