Carb Metabolism

Question 1

Taruai Disease

Answer 1

PFK1 deficiency. No ATP. muscle weakness Hemolytic anemia from Na pumps requiring ATP.

Question 2

Hemolytic anemia

Answer 2

most common from glycolytic enzyme defects, 95% time PK. Na pumps requiring ATP don’t function right. Na+ pulls water into cell lysing it.

Question 3

PFK2 kinase active

Answer 3

Insulin. Dephosphorylated. Produces F2,6BP that activates PFK1

Question 4

PFK2 phosphatase active

Answer 4

Glucagon. Phosphorylated. F2,6BP converted to F6P and sent to gluconeogenesis. glycolysis decreased.

Question 5

gluconeogenesis location

Answer 5

Liver, kidney and small intestine

Question 6

Malate dehydrogenase

Answer 6

Converts OAA to Malate oxidizing NADH in mitochondria of Gluconeogenesis. Converts Malate back to OAA reducing NAD+ in cytosol. COMMITMENT check for gluconeogenesis.

Question 7

Pyruvate carboxylase and cofactor

Answer 7

Biotin cofactor. ATP dependent. Converts Pyruvate to OAA using ATP in mitochondria for gluconeogenesis. 1st irreversible glycolytic step bypassed.

Question 8

PEP carboxylase

Answer 8

Converts OAA to PEP in cytosol of gluconeogenesis. 2nd glycolytic Step Bypassed.

Question 9

Fructose 1,6 bisphopsphatase

Answer 9

Converts F1,6BP to F6P by removing a phosphate in gluconeogenesis. RATE LIMITING and 3rd glycolytic bypassed step.

Question 10

Glucose 6 phosphatase function and name both pathways

Answer 10

converts G6P to Glucose by removing a phosphate. SKIPS HEXO/GLUCOKINASE

4th and last glycolytic step passed during gluconeogenesis.

Glycogenolysis - liver uses it to make glucose

Question 11

glycolytic intermediates used in gluconeogenesis

Answer 11

PEP converted to pyruvate when ATP high/glucagon present.

F2,6BP converted to F6P when glucagon high

Question 12

F1,6BP deficiency

Answer 12

Similar to tarui disease (PFK1 deficiency)(glycolysis). F1,6BP deficiency results inability to complete gluconeogenesis and results in hypoglycemia and lactic acid buildup from cori cycle.

Question 13

Cori Cycle

Answer 13

oxygen cannot keep up with ATP need in muscle. Anerobic glycolysis produces ATP and lactate. Lactate sent from muscle to liver, recycled into glucose, and sent back to muscle. Unsustainable over time.

Question 14

Gluconeogenesis precursors

Answer 14

Fructose
Galactose
Glycogen - glycogenolysis
glycerol - FAs
Lactate - Cori Cycle
AA's - TCA intermediates converted to malate

Question 15

Von Gierke disease (GSD1a) gluconeogenesis

Answer 15

G6P deficiency results in lack of glucose being produced from gluconeogenesis. hypoglycemia.

Question 16

GLUT 1

Answer 16

High glucose affinity. brain

Question 17

GLUT 3

Answer 17

high glucose affinity. neurons

Question 18

Glut 4

Answer 18

Medium glucose affinity. Skeletal muscle. heart.

Question 19

Glut 2

Answer 19

Low glucose affinity. liver pancrease.

Question 20

Glucose + fructose

Answer 20

Sucrose

Question 21

Galactose + glucose

Answer 21

Lactose

Question 22

Fructose enterocyte absorption

Answer 22

GLUT5

Question 23

Fructose basolateral transport protein into blood

Answer 23

GLUT2 and GLUT5

Question 24

SGLT1

Answer 24

enterocyte membrane protein absorbs galactose and glucose

Question 25

Fructose, galactose, and glucose transport protein from enterocyte basolateral membrane into blood

Answer 25

GLUT2

Question 26

aldose reductase

Answer 26

reduces glucose to sorbitol

Question 27

enzyme responsible for oxidizing sorbitol to fructose

Answer 27

sorbitol dehydrogenase

Question 28

Sorbitol dehydrogenase deficiency

Answer 28

sorbitol accumulation in liver, ovaries, seminal vesicles, and causes water influx

Question 29

Why is fructose metabolism faster

Answer 29

bypasses Rate limiting step of glycolysis (No PFK1 or PFK2 modulation)

Question 30

Product of fructose metabolism

Answer 30

TAGS

Question 31

Polyol pathway

Answer 31

Glucose to fructose. Sorbitol intermediate. Glucose reduced to sorbitol via aldose reductase (NAD+ produced), sorbitol oxidized to fructose via sorbitol dehydrogenase (NADH produced).

Question 32

Physiological effect of excess fructose

Answer 32

increase glycerol and acetyl coa which increased Fatty acid. fatty liver disease

Question 33

Lactose intolerance

Answer 33

Deficiency in Lactase. inability to breakdown lactose to glucose and galactose

Question 34

deficiency of galactose 1-phosphate uridyl transferase (GALT)

Answer 34

Inability to do galactose metabolism. increased galactose and galactitol.

Question 35

Defective Galactose kinase

Answer 35

Increased galactose and galactitol inblood.

Question 36

PPP products

Answer 36

2 NADPH and Ribulose 5-phosphate

Question 37

Use of ribulose 5-phosphate

Answer 37

sugar backbone of DNA/RNA

Question 38

use of NADPH from ppp

Answer 38

reductive biosynthesis (FA and steroid synthesis) and reduction agent used to combat oxidative stress from infections and agents like h2O2.

Question 39

What pathways can the end products of the non-oxidative phase of PPP go into

Answer 39

F6P and G3P can enter glycolysis or gluconeogenesis ribose 5-phosphate can enter nucleotide synthesis

Question 40

High ppp activity in which two cell types and why?

Answer 40

phagocytic because of need for NADPH in oxidative burst capabilities. lactating mammary glands is fatty tissue and NADPH is needed for each FA.

Question 41

bond types in glycogen

Answer 41

a1,4 for elongationand a1,6 for branching

Question 42

glycogen is extended and degraded from which end

Answer 42

non-reducing end/terminal end

Question 43

glycogenin

Answer 43

reducing end of glycogen. acts as a primer to start glycogen chain

Question 44

How is glycogen stored

Answer 44

granules

Question 45

where is majority of glycogen stored

Answer 45

liver and muscle

Question 46

glycogen granules contain glycogen and ...

Answer 46

enzymes needed for metabolism

Question 47

Regulates blood glucose levels

Answer 47

liver glycogen storage

Question 48

glucokinase/hexokinase role in glycogen synthesis

Answer 48

trapping glucose in the cell via phosphorylation. just like glycolysis

Question 49

phosphoglucomutase

Answer 49

glycogenesis. Converts G6P to G1P. SIMILAR TO GLYCOLYSIS. phosphoglucase isomerase normally converts G6P to F6P. its a mutase because not an isomer.

Question 50

UDP glucose pyrophosphorylase

Answer 50

activates G1P to UDP glucose to be added to glycogen chain

Question 51

glycogen synthase

Answer 51

Adds UDP glucose to non-reducing end of glycogen chain via 1,4

Question 52

glucosyl transferase

Answer 52

After 11 UDP glucose residues added to 1,4 chain it removes 7 of these and adds them as 1,6 branches

Question 53

rate limiting enzyme glycogenolysis

Answer 53

Glycogen phoshporylase

Question 54

Rate limiting enzyme of glycogenesis

Answer 54

Glycogen synthase

Question 55

Purpose of glycogen metabolism

Answer 55

blood sugar | energy to muscle

Question 56

phosphorylation status of active glycogen synthase

Answer 56

dephosphorylated

Question 57

phosphorylation status of active glycogen phosphorylase

Answer 57

phosphorylation active

Question 58

glycogenesis favored during which metabolic state

Answer 58

FED = high blood glucose, high insulin, high ATP

Question 59

Glycogenolysis favored during what physiological state

Answer 59

``` fasting = low blood glucose, high glucagon, high AMP Excercise = high cellular calcium in muscles ```

Question 60

Rate limiting step in PPP

Answer 60

G6P dehydrogenase. converts G6P to something not important

Question 61

Enzyme that converts galactose to Galactose 1-P in galactose metabolism

Answer 61

Galactokinase

Question 62

Rate limiting step/enzyme of galactose metabolism

Answer 62

GALT converting Galactose 1 P to G6P. G6p will then do reverse glycolysis and convert G6P to glucose by skipping hexokinase.

Question 63

ATP consuming steps of glycolysis

Answer 63

1 and 3. Hexokinase and PFK-1

Question 64

NADH producing step of glycolysis

Answer 64

6. GAPDH converts G3P to 1,3 bpg.

Question 65

ATP producing steps of glycolysis

Answer 65

7. phosphoglucose mutase converts 1,3 bpg to 3pg | 8. Pyruvate kinase converts PEP to pyruvate