fuels Flashcards
(30 cards)
describe catabolism of fatty acids inducing beta oxidation and energy yield
why can the body not store excess amino acids
explain the process of deamination ad the fate of nitrogen containing compounds
explain the metabolic fates of the resulting carbon skeletons
compare and contrast ATP production mechanisms aerobic and anaerobic conditions
why is lactic acid fermentation important in regenerating NAD plus for glycolysis
compare the substrate utilisation in skeletal muscle, cardiac muscle, brain and red blood cells
brain: glucose and ketone Bodies- available glucose during fasting state is prioritised for the brain
skeletal muscle; fatty acids, glucose and ketone bodies
heart muscle: fatty acids, lactate and ketone bodies
red blood cells: glucose
explain how tissue specific preferences for metabolic substrate change during fed, fasting and starvation state
skeletal muscle- glucose in fed sate, fattily acids during rest and mild intensity exercise, glucose with high intensity exercise
heart- mostly fatty acids during fasting state
red blood cells- no mitochondria and rely on glycolysis and lactic acid fermentation
why is pyruvate turned into lactate
its not oxidised into cytacolae, its turned into lactic acid through lactic acid fermentation
do you get ATP produced in lactic acid fermentation
no.
how does lactic acid fermentation work
when pyruvate (under oxygen limiting condition) it converts to lactate
how can glycolysis continue to be performed during oxygen limiting conditions
you oxidise NADH into NAD, you can then use the NAD energy for glycolysis and be reduced again and glycolysis can keep happening
what are fatty acids made of
long chains of hydrocarbons. fatty acid chains can vary in number. they all have even number of carbons.
how do you oxidise fatty acids
beta oxidation- you cleave ff two carbon atoms at a time. this two carbons, you are forming acetyl CoA.
how does glucose and fatty acids vary in providing acetyl CoA
as fatty acids are bigger, you can produce more. therefore you produce more ATP.
does aerobic metabolism of glucose produce more than anaerobic metabolism
yes.
what do you need to oxidise fatty acids
oxygen because all the products from the fatty acids oxidisation goes into the Krebs cycle and takes it to the electron transport chain which directly uses it.
how can you dial get fatty acids if ou don’t have a high fat diet
Acetyl CoA high is made from fatty acids can be converted back into acetyl CoA.
aside from being turned back into fatty acids, what else can acetyl coA be turned dinto
ketone bodies- as we consume triglycerides and this will make a bunch of acetyl coA, this is too much for the body and so is stored as ketone bodies (produced in the liver)
under starvation conditions, what happens to ketone bodies
it turns into acetyl CoaA again to the Krab cycle and used for other parts of the body that need it like the brain
explain the difference in the molecules that make up carbohydrates, fats and amino acids
carbohydrates: carbon, hydrogen and oxygen
fats- carbon and hydroge
amino acids: amino group and acid group nitrogenous and non. what makes them unit is the side chain.
what are the two types of amino acids classified as
amino acids are degraded through reanimation that produces two types of sugars:
glucogenic: precursors to generate glucose like pyruvate
ketogenic: converted to ketone bodies, turned into acetyl CoA.
how is glucogenic important during fasting state
they can generate glucose. its also important during times we don’t have oxygen because it makes pyruvate which can make lactic acid through lactation fermentation
how do we make glucogenic or ketogenic
deamination: forming carbon like structures. you want to eliminate nitrogenous portion. the nitrogenous portion combines with hydrogen to form ammonia- toxic which is secreted through the urea. this mostly happens in the liver and some in the kidney. the non nitrogenous portion becomes the carbon skeleton
