INTEGRATION OF METABOLISM Flashcards
Stimulus for secretion of INSULIN
- Ingestion of glucose and amino acids
- Cholecystokinin and gastricinhibitory polypeptide
What is the transporter of Fructose in the enterocytes?
GLUT 5
SGLT - 1 transport what substances?
Na, Glucose and Galactose
Where are bile salts absorbed?
ileum (enterohepatic circulation)
Enzymes in the fasting state should be __________ for them to be active.
PHOSPHORYLATED.
In the oral cavity, what digests glycogen and starch, yielding short branched and unbranched oligosaccharides called dextrins?
Salivary α-amylase
Majority of absorption of monosaccharides occurs in the ____
duodenum and upper jejunum
Ketogenesis and ketolysis happens both in the fasting state. TRUE or FALSE.
TRUE
In the jejunum, free fatty acids, cholesterol, 2-monoacylglycerols, and fat-soluble vitamins form disk-shaped ________, which come in contact with the epithelium by the enterocytes, allowing absorption.
mixed micelles
What transporters are present in the APICAL MEMBRANE / LUMINAL SIDE of the enterocytes?
SGLT-1 and GLUT 5
Fructose is absorbed in the enterocytes via what transport mechanism?
facilitated diffusion
* This does not require ATP, and the transport protein is GLUT 5.
RBC’s source of fuel during fed and fasting state.
Use glucose exclusively as fuel coz they don’t have mitochondria
In the endoplasmic reticulum of enterocytes, the dietary lipids are converted back to TAGs and cholesteryl esters and are packaged as _______ and released into the lymphatic circulation (lacteals).
chylomicrons
Pathways increased in the well fed state
- Glucose uptake
- Glycogenesis
- Protein synthesis
- Lipogenesis
Stimulus for secretion of GLucagon
Actual or potential hypoglycemia
_______ located on the brush border releases free amino acids from dipeptides and oligopeptides
Aminopeptidases
True or false. Short- and medium-chain fatty acids are absorbed without the need for micelles.
TRUE
in the SI, what digests TAGs (into 2-monoacylglycerols and 2 free fatty acids)?
Pancreatic lipase
Free amino acids are taken to the portal circulation via what transport mechanism out of the enterocytes?
facilitated diffusion
Gluconeogenesis happens in what organs?
Liver and Kidney
2ND MESSENGER OF GLUCAGON
cAMP
GLUT 2 transports what substances?
Glucose, Galactose and Fructose
In the SI, what digests choleteryl esters (into cholesterol and fatty acid)?
cholesteryl ester hydrolase
Enzymes in the well fed state should be __________ for them to be active.
DEPHOSPHORYLATED
Pathways increased in the fasting state
- Gluconeogenesis
- Glycogenolysis
- Uptake of amino acids
- Beta-oxidation
- Ketogenesis
glucose and galactose are transported into the enterocytes (intestinal mucosal cells) via what transport mechanism?
secondary active transport
*This requires ATP. Glucose and galactose are transported with the Na+ ion, through the transport protein SGLT.
2nd messenger of insulin
Tyrosine kinase
________ activates trypsinogen, and trypsin is capable of activating all the rest, including itself
Enteropeptidase
What transporters are present in the BASOLATERAL MEMBRANE of the enterocytes?
GLUT-2
What are the sources of fuel of the brain during fasting?
glucose and ketone bodies
Principal site of metabolism of branched chain amino acids
Skeletal muscles
Free amino acids in the enterocytes are absorbed via what transport mechanism?
secondary active transport, coupled with Na +
(Note: secondary active pag iaabsorb pa lang sa enterocyte; facilitated diffusion pag lalabas na ng enterocyte to go to portal circulation. )
glycogen stores lasts only for how many hourrs
18 - 24 hrs
