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Whats wrong with Elisa? - presentationDiscuss how the body uses stored energy (in the form of carbohydrates, fats and

proteins)

1. After 30 minutes of intensive exercise some hours after a carbohydraterich meal

2. Early in the morning before breakfast (12 hours after last meal)1. After intensive exercise

CARBOHYDRATE

DURING EXERCISE

- Because theres a lack of oxygen in muscles, energy is provided byanaerobic pathways i.e. glycolysis

- During glycolysis: glycogen is broken down into glucose, which is thencan be converted into pyruvate, producing energy in the form of ATP

- Glycogen mobilization happens in the body, where glucose gets releasedfrom the liver, all this glucose can undergo glycolysis to provide energyfor the body as ATP

- Glycolysis is a two phased process; during preparatory phase, for everyglucose molecule (obtained from the breaking down of glycogen), 2

glyceraldehyde 3 phosphate (G3P) molecules are formed, this process

uses 2 ATP molecules during phosphorylation; payoff phase, for every

glyceraldehyde 3 phosphate (G3P) molecule, 2 pyruvate molecules are

formed as well as 4 ATP as the result. Therefore net production is 2 ATP

- During exercise, oxygen is gained and aerobic pathways are utilized- Pyruvate is converted into Acetyl CoA under the effect of enzyme

pyruvate dehydrogenase, producing NADH and CO2

- Citric acid cycle- Each Acetyl CoA reacts with oxaloacetate to form acetate, resulting in

production of 2 molecules of CO2, 1 molecule of GTP, sources of energy

for gluconeogenesis

- One Acetyl CoA molecule produces 10 ATP molecules- Elisas glucose amountin her blood is high can suggest either a failure in

her body function of breaking down glucose or she just have had a meal

when the test was done. If there is indeed a failure with her glucose

regulation in her body, this can indicate that she might have type I

diabetes mellitus, which means that her body lacks beta cells that can

release insulin which triggers glucose uptake by other cells of the body

- Glucose will keep accumulating a condition known as hyperglycemiaFAT

- Body is low on glucose, hence switches to metabolism of fats- Fats are stored in adipose tissue hence they need to be mobilized before

undergoing further reaction

- Enzyme triacylglycerol lipase is activated, this enzyme catalyses theprocess of converting fats in adipose tissue into glycerols and fatty acids

- Glycerols are transported back to the liver by serum albumin, whilst fattyacid is left to undergo beta oxidation to form acetyl CoA in the

mitochondria

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- Acetyl CoA is released and can either enter the citric acid cycle directly, orcan undergo a conversion to form ketone bodies

- On the other hand, glycerol is converted into glycerol 3 phosphate, aprocess utilizing ATP

- Glycerol 3 phosphate can be converted into dihydroxyacetone phosphate,which can isomerise into glyceraldehyde 3 phosphate, which can continueto enter the payoff phase of glycolysis

PROTEINS

Exercise:

- Catabolism of amino acids gives rise to the intermediate compounds ofcitric acid cycle

- Alanine, serine, cysteine and asparagine are converted to oxaloacetate- Glutamine, proline, arginine and histidine are converted into alpha

ketoglutarate through glutamate

- Succinyl CoA can be turned into non polar amino acids like methione,valine and isoleucine

- Leucine is degraded to acetyl CoA and acetoacetate- Tryptophane, lysine, leucine, phenylalanine, tyrosine and isoleucine

donate their carbons to acetyl CoA

- The urea and citric acid cycles are interconnected, as fumarate producedin argininosuccinate in the urea cycle is also an intermediate of the citric

acid cycle

After a meal:- Pepsinogen an active precursor or zymogen is converted into active

pepsin

- In the stomach, pepsin hydrolyses ingested proteins at peptide bonds onthe amino terminal side of the aromatic amino acid residues Phe, Trp, and

Tyr, cleaving long polypeptide chains into a mixture of smaller peptides

- Low pH triggers secretion of the hormone secretin into the blood- Secretin stimulates the pancreas to secrete bicarbonate into small

intestine to neutralize the gastric HCl, abruptly increasing the pH to about

7.

- Arrival of amino acids in the upper part of the intestine (duodenum)causes release into the blood of the hormone cholecystokinin, stimulates

secretion of several pancreatic enzymes

- Trypsinogen, chymotrypsinogen and procarboxypeptidases A and B,zymogens of trypsin, chymotrypsin, and carboxypeptidases

- Synthesis of the enzymes as inactive precursors protects the exocrinecells from destructive proteolytic attack

2. Early morning before breakfast- Similar to when it is exercising, the body will break down glucose andfatty acids in order to obtain energy

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- However, depending on the amount of hours its spent in starvation, thebody will decide whether to break down glycogen or body fat

- If it senses that the amount of glycogen is running low, it will break downketone bodies, which are formed by conversion of acetyl CoA

- Elisas ketone body level is high in her body, which makes sense becauseshe hasnt had any meal recently however, her glucose level is also high.Here we can conclude that she might have problem with glucose

regulation, or it might be because of her diet/incorrect techniques/the

time she takes the home diagnostic tests during the day

- During starvation, the body will prefer to burn down fat reserves first,and only consumes glucose/proteins when they are exhausted. After a

prolonged period of starvation, the body will utilize proteins as a fuel

- Pepsinogen an active precursor or zymogen is converted into activepepsin

- In the stomach, pepsin hydrolyses ingested proteins at peptide bonds onthe amino terminal side of the aromatic amino acid residues Phe, Trp, and

Tyr, cleaving long polypeptide chains into a mixture of smaller peptides

- Low pH triggers secretion of the hormone secretin into the blood- Secretin stimulates the pancreas to secrete bicarbonate into small

intestine to neutralize the gastric HCl, abruptly increasing the pH to about

7.

- Arrival of amino acids in the upper part of the intestine (duodenum)causes release into the blood of the hormone cholecystokinin, stimulates

secretion of several pancreatic enzymes

- Trypsinogen, chymotrypsinogen and procarboxypeptidases A and B,zymogens of trypsin, chymotrypsin, and carboxypeptidases

- Synthesis of the enzymes as inactive precursors protects the exocrinecells from destructive proteolytic attack