metabolic pathways and ATP production

Question 1

3 stages of cellular metabolism

Answer 1

proteins → amino acids; polysaccharides → simple sugars; fats → fatty acids and glycerol

Question 2

3 stages of cellular metabolism

Answer 2

diagram from metabolism 3

Question 3

metabolic reactions: H-GRAIL

Answer 3

Hydrolytic (cleave bonds by +H2O); Group transfer (transfer of functional group); Redox (e- transfer); Adding/removing functional groups (+/- to -/+ double bonds); Isomerisation (rearrange atoms); Ligation with ATP cleavage (forming covalent bonds)

Question 4

effect of having a meal on metabolism: [blood glucose], insulin, glucagon, glucose uptake, triglyeride synthesis, use of metabolic intermediates

Answer 4

{blood glucose] initially rises; insulin increases; glucagon decreases; increase glucose uptake by liver (glycogen and glycolysis as acetyl CoA → FA synthesis); increase triglyceride synthesis in adipose; increase use of metabolic intermediates

Question 5

effect after a meal on metabolism: [blood glucose], glucagon, insulin, glucose production, fatty acid breakdown

Answer 5

[blood glucose] decreases; glucagon increases; insulin decreases; glucose produced via glycogenolysis and gluconeogenesis; FA breakdown for B-oxidation

Question 6

effect of prolonged fasting on metabolism: glucagon, insulin, triglycerides, TCA intermediates, protein, ketone bodies

Answer 6

glucagon increases; insulin decreases further; adipose hydrolyses triglycerides → FA (B-oxidation); TCA intermediates reduced so more available for gluconeogenesis; protein breakdown provides amino acids for gluconeogenesis; ketone bodies produced from FA and amino acids in liver for brain