INTEGRATION OF METABOLISM

Question 1

Stimulus for secretion of INSULIN

Answer 1

• Ingestion of glucose and amino acids
• Cholecystokinin and gastricinhibitory polypeptide

Question 2

What is the transporter of Fructose in the enterocytes?

Answer 2

GLUT 5

Question 3

SGLT - 1 transport what substances?

Answer 3

Na, Glucose and Galactose

Question 4

Where are bile salts absorbed?

Answer 4

ileum (enterohepatic circulation)

Question 5

Enzymes in the fasting state should be __________ for them to be active.

Answer 5

PHOSPHORYLATED.

Question 6

In the oral cavity, what digests glycogen and starch, yielding short branched and unbranched oligosaccharides called dextrins?

Answer 6

Salivary α-amylase

Question 7

Majority of absorption of monosaccharides occurs in the ____

Answer 7

duodenum and upper jejunum

Question 8

Ketogenesis and ketolysis happens both in the fasting state. TRUE or FALSE.

Answer 8

TRUE

Question 9

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.

Answer 9

mixed micelles

Question 10

What transporters are present in the APICAL MEMBRANE / LUMINAL SIDE of the enterocytes?

Answer 10

SGLT-1 and GLUT 5

Question 11

Fructose is absorbed in the enterocytes via what transport mechanism?

Answer 11

facilitated diffusion

* This does not require ATP, and the transport protein is GLUT 5.

Question 12

RBC’s source of fuel during fed and fasting state.

Answer 12

Use glucose exclusively as fuel coz they don’t have mitochondria

Question 13

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).

Answer 13

chylomicrons

Question 14

Pathways increased in the well fed state

Answer 14

• Glucose uptake
• Glycogenesis
• Protein synthesis
• Lipogenesis

Question 15

Stimulus for secretion of GLucagon

Answer 15

Actual or potential hypoglycemia

Question 16

_______ located on the brush border releases free amino acids from dipeptides and oligopeptides

Answer 16

Aminopeptidases

Question 17

True or false. Short- and medium-chain fatty acids are absorbed without the need for micelles.

Answer 17

TRUE

Question 18

in the SI, what digests TAGs (into 2-monoacylglycerols and 2 free fatty acids)?

Answer 18

Pancreatic lipase

Question 19

Free amino acids are taken to the portal circulation via what transport mechanism out of the enterocytes?

Answer 19

facilitated diffusion

Question 20

Gluconeogenesis happens in what organs?

Answer 20

Liver and Kidney

Question 21

2ND MESSENGER OF GLUCAGON

Answer 21

cAMP

Question 22

GLUT 2 transports what substances?

Answer 22

Glucose, Galactose and Fructose

Question 23

In the SI, what digests choleteryl esters (into cholesterol and fatty acid)?

Answer 23

cholesteryl ester hydrolase

Question 24

Enzymes in the well fed state should be __________ for them to be active.

Answer 24

DEPHOSPHORYLATED

Question 25

Pathways increased in the fasting state

Answer 25

• Gluconeogenesis
• Glycogenolysis
• Uptake of amino acids
• Beta-oxidation
• Ketogenesis

Question 26

glucose and galactose are transported into the enterocytes (intestinal mucosal cells) via what transport mechanism?

Answer 26

secondary active transport

*This requires ATP. Glucose and galactose are transported with the Na+ ion, through the transport protein SGLT.

Question 27

2nd messenger of insulin

Answer 27

Tyrosine kinase

Question 28

________ activates trypsinogen, and trypsin is capable of activating all the rest, including itself

Answer 28

Enteropeptidase

Question 29

What transporters are present in the BASOLATERAL MEMBRANE of the enterocytes?

Answer 29

GLUT-2

Question 30

What are the sources of fuel of the brain during fasting?

Answer 30

glucose and ketone bodies

Question 31

Principal site of metabolism of branched chain amino acids

Answer 31

Skeletal muscles

Question 32

Free amino acids in the enterocytes are absorbed via what transport mechanism?

Answer 32

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. )

Question 33

glycogen stores lasts only for how many hourrs

Answer 33

18 - 24 hrs