Metabolism Flashcards
what are the 2 purposes of catabolic pathways?
- capture energy in the form of reduced compounds
2. convert molecules into building blocks so they can become more complex molecules
what are the 3 steps of energy generation in catabolic pathways?
- hydrolysis of complex molecules to component building blocks
- conversion of building blocks to simple intermediates
- oxidation of acetyl CoA
what is the only metabolic level that decreases in the absorptive state?
glucagon
what is the glucose transporter to the liver and is it insulin insensitive or sensitive?
GLUT-2
insensitive
what levels are altered because of amino acids taken up by the liver?
increased amino acid degradation
increased protein synthesis
what levels are altered because of the carbs taken up by the liver?
increased glycogen synthesis
increased HMP pathway
increased glycolysis
DECREASED gluconeogenesis
what transporter helps get glucose into adipose tissue and is it insulin sensitive or insensitive?
GLUT-4
sensitive
what levels are altered because of the lipids taken up by the liver?
increased fatty acid synthesis
increased TAG synthesis
what levels are affected because of carbohydrate metabolism by the adipose tissue?
increased glucose transport
increased glycolysis
what levels are affected by fat metabolism in adipose tissue?
increased TAG synthesis
decreased TAG degradation (inactive lipase)
what levels are affected by carbohydrate metabolism in muscle?
increased glycogen synthesis
increased glucose transport
what transporter gets glucose into muscle tissue and is it insulin sensitive or insensitive?
GLUT-4
sensitive
what compound can the liver NOT metabolize that the muscle tissue can?
branched chain amino acids
what levels are affected by amino acid metabolism in muscle tissue?
increased protein synthesis
increased branched chain amino acid synthesis
what are the sources of fuel the heart will use in order of most desirable to least desirable?
fatty acids
glucose
ketones
what source of fuel can the brain NOT use because of the BBB?
fatty acids
what are the 2 main priorities of your key metabolic organs during fasting?
- maintain blood glucose levels for tissues requiring glucose
- mobilize fatty acids and ketones to get energy to other tissues
what is the main role of the liver during fasting?
maintain blood glucose
what is the first and second source of glucose provided by the liver through carbohydrate metabolism?
1st- glycogen
2nd- gluconeogensis
what does ketogenesis by the liver in prolonged starvation do?
provide ketone bodies that the peripheral tissues can use as fuel
what levels are affected in the fasting state by fat metabolism in adipose tissue?
increased degradation of TAG
decreased uptake of fatty acids
increased release of fatty acids
what fuel sources does the brain use in fasting?
glucose the first few days
after 2-3 weeks- mostly ketones
what are the 2 key functions of the kidney in fasting?
perform gluconeogenesis (make glucose) keep pH balanced by metabolizing glutamine that produces ammonia
