Lecture 16 - Gluconeogenesis

Question 1

Whole body needs […] glucose per day.

Answer 1

160 g

Question 2

Daily glucose requirement of brain.

Answer 2

120 g

Question 3

Glucose present in body fluids.

Answer 3

20 g

Question 4

Glucose readily available from glycogen is […].

Answer 4

190 g

Question 5

Location of gluconeogenesis.

Answer 5

Liver and kidney

Question 6

Gluconeogenesis converts […] to […].

Answer 6

Pyruvate; Glucose

Question 7

Major precursors of gluconeogenesis.

Answer 7

Lactate, amino acids, and glycerol

Question 8

Enzyme of gluconeogenesis, converts pyruvate to oxaloacetate (OAA).

Answer 8

Pyruvate carboxylase

Question 9

Location of pyruvate carboxylase.

Answer 9

Mitochondria (i.e. significance = All other enzymes in the cytoplasm)

Question 10

Method by which OAA is transported to cytoplasm.

Answer 10

Malate shuffle

Question 11

Enzyme of gluconeogenesis, converts GAP + DHAP to fructose 1,6-bisphosphate.

Answer 11

Fructose 1,6-bisphosphatase

Question 12

Rate limiting enzyme of gluconeogenesis.

Answer 12

Fructose 1,6-bisphosphate

Question 13

Enzyme of gluconeogenesis, converts Glucose 6-phosphate to glucose.

Answer 13

Glucose 6-phosphatase

Question 14

Location of glucose 6-phosphatase.

Answer 14

Endoplasmic reticulum

Question 15

Protein, transports glucose 6-phosphate to ER.

Answer 15

T1

Question 16

Protein, transports inorganic phosphate back into cytosol.

Answer 16

T2

Question 17

Protein, transports glucose back to cytoplasm.

Answer 17

T3

Question 18

Four enzymes of gluconeogenesis, not found in glycolysis, by-pass the irreversible steps of glycolysis.

Answer 18

Pyruvate carboxylase, phosphoenolpyrubate carboxykinse, fructose 1,6-bisphosphate, and glucose 6-phosphate

Question 19

3 enzymes of gluconeogenesis that utilize ATP/GTP.

Answer 19

Pyruvate carboxylase, phosphoenolpyruvate carboxykinase, phosphoglycerate kinase.

Question 20

[…] determines which pathway will be most active (i.e. gluconeogenesis or glycolysis).

Answer 20

Energy charge (i.e. ATP/ADP ratio)

Question 21

Gluconeogenesis and glycolysis are […] regulated.

Answer 21

Reciprocally

Question 22

Glycolysis is favored when blood […] is high.

Answer 22

Insulin

Question 23

Gluconeogenesis is favored when blood […] levels are low and glycogen stores are depleted.

Answer 23

Gluconeogenesis

Question 24

Tissue location of gluconeogenesis.

Answer 24

Liver, kidneys, small intestine

Question 25

Positive regulators of glycolysis.

Answer 25

Glucose, insulin, AMP, Fructose 2,6-Bisphosphate, Fructose 1,6-Bisphosphate

Question 26

Positive regulators of gluconeogenesis.

Answer 26

Glucagon, citrate, cortisol, thyroxine, acetyl CoA

Question 27

Negative regulators of glycolysis.

Answer 27

Glucagon, ATP, citrate, Glucose 6-Phosphate, Fructose 6-Phosphate, alanine

Question 28

Negative regualtors of gluconeogenesis.

Answer 28

ADP, ANP, Fructose 2,6-Bisphosphate

Question 29

Enzyme, converts fructose 6-phosphate to fructose 2,6-bisphosphate which stimulates PFK.

Answer 29

Phosphofructokinase 2

Question 30

Bi-functional enzyme, stimulated/inhibited via concentration of fructose 2,6-bisphosphate allowing for the control of glycolysis.

Answer 30

Phosphofructokinase 2 and fructose bisphosphate 2

Question 31

Hormonal control of phosphofructokinase 2 and fructose bisphosphatase 2.

Answer 31

Insulin and glucagon

Question 32

Process, lactate produced in skeletal muscle/RBCs is converted back to pyruvate in the liver (i.e. pyruvate can enter gluconeogenic pathway and regenerate glucose)

Answer 32

Cori cycle