Overview of Metabolism Flashcards
catabolic
breakdown of compounds to produce energy
examples of catabolic pathways
glycolysis, TCA cycle, oxidative phosphorylation, fatty acid catabolism, amino acid oxidation
anabolic
use energy to produce biomolecules
anabolic pathways
gluconeogenesis, lipid biosynthesis, amino acid biosynthesis, nucleotide biosynthesis
regulated steps
reactions are far from equilibrium (can not go forward and reverse with same molecules)
allosteric effectors mediate _
local effects (cell status)
hormones mediate _
systemic effects (needs of body/organism)
glycolysis
glucose –> 2 pyruvate
gluconeogenesis
pyruvate –> glucose
What stimulates PFK?
F2,6BP and AMP
What inhibits PFK?
ATP, citrate, H+
What inhibits F-1,6-bisphosphatase?
F2,6BP and AMP
What stimulates F-1,6-bisphosphatase?
citrate
What activates pyruvate kinase?
F-1,6-BP
What inhibits pyruvate kinase?
ATP and alanine
What activates pyruvate carboxylase?
acetyl CoA
pyruvate carboxylase
pyruvate –> oxaloacetate
What inhibits pyruvate carboxylase?
ADP
What inhibits PEP carboxykinase?
ADP
PEP carboxykinase
oxaloacetate –> PEP
proteins kcal
4kcal/gram
carbohydrates kcal
4kcal/gram
fats kcal
9 kcal/gram
US dietary guidelines
45-65% carbohydrates
10-35% proteins
>10% fats
energy balance equation
calories consumed-calories used
biggest factor in weight gain
carbohydrates
biggest factor in weight loss
resting metabolic rate
average male calorie intake
2700 kcal/day
average female calorie intake
2200 kcal/day
resting metabolic calorie use
60-70% of total calories (20% in brain)