117 Bfcp2A Biochemistry Glucose Homeostasis

Front 1

where does gluconeogenesis occur

Back 1

primarily in the liver (a small amount in kidney for kidney)

Front 2

1st reaction of gluconeogenesis

Back 2

pyruvate to oxaloacetate (via pyruvate carboxylase)

Front 3

protein that binds biotin in raw egg white

Back 3

avidin

Front 4

enzyme that converts OAA to PEP

Back 4

PEPCK (utilizes GTP as well)

Front 5

mechanism by which OAA gets transported out of mitochondria

Back 5

conversion to malate or aspartate and reconversion to OAA

Front 6

an inducible enzyme that is needed for tissues to make a lot of glucose (plays a role in gluconeogenesis via pyruvate)

Back 6

PEPCK (induced by cAMP)

Front 7

dephosphorylates fructose 1,6-bisphosphate during gluconeogenesis

Back 7

fructose 1,6-bisphosphatase

Front 8

removes phosphate from glucose-6-P as the last step in gluconeogenesis (located on membrane of ER, not cytosolic)

Back 8

glucose-6-phosphatase

Front 9

responsible for generation of most lactate during the day

Back 9

RBCs

Front 10

process that converts lactate from muscle to glucose inl iver

Back 10

cori cycle

Front 11

generates glucose from branched chain amino acids and pyruvate in muscle tissue via transporting alanine to the liver (alanine is converted to pyruvate first, and NH2 is excreted via liver)

Back 11

glucose-alanine cycle

Front 12

amino acids which are not glucogenic

Back 12

leucine and lysine

Front 13

how can glycerol be converted to glucose

Back 13

by using the reverse process of glycolysis

Front 14

what are some conditions that impair gluconeogenesis

Back 14

anemia and alcohol (cause shift of NAD+ to NADH)

Front 15

what are the energetic costs of gluconeogenesis from pyruvate

Back 15

6 ATP and 2 NADH

Front 16

Where does the energy input for gluconeogenesis come from primarily?

Back 16

β-oxidation of fatty acids

Front 17

how do corticosteroid drugs stimulate gluconeogenesis?

Back 17

they cause the breakdown of muscle protein to amino acids and induce PEPCK

Front 18

key enzymes in fructose metabolism pathway

Back 18

fructose kinase, aldolase B, triose kinase

Front 19

common intermediates between fructose metabolism and glycolysis

Back 19

DHAP and glyceraldehyde-3-P

Front 20

What enzyme splits fructose 1-P?

Back 20

aldolase B

Front 21

What does aldolase B split fructose 1-P into?

Back 21

dihydroxyacetone-P and glyceraldehyde

Front 22

How is the glyceraldehyde intermediate of fructose metabolism converted into a molecule that can enter gluconeogenesis?

Back 22

It's phosphorylated via triose kinase and an ATP into glyceraldehyde-3-P which is a direct intermediate of glycolysis/gluconeogenesis.

Front 23

What's the first step in fructose metabolism?

Back 23

Phosphorylation of fructose to fructose-1-P via fructokinase and an ATP.

Front 24

Where does fructose metabolism occur?

Back 24

in the liver

Front 25

What’s the cause of hereditary fructose intolerance?

Back 25

an aldolase B defect that causes fructose-1-P to accumulate and ATP to decrease

Front 26

What are the complications of hereditary fructose intolerance?

Back 26

F-1-P accumulation impairs glycolysis, gluconeogenesis and glycogen breakdown and may damage the liver (also throws off phosphate levels)

Front 27

What's a common form of fructose insufficiency that leads to fructose in the urine and may cause cataracts?

Back 27

fructokinase deficiency

Front 28

What's the most common form of fructose intolerance?

Back 28

inability to absorb fructose from the gut

Front 29

What step of glycolysis.gluconeogenesis does fructose-1-phosphate interfere with?

Back 29

conversion between fructose-1,6-phosphate and DHAP/glyceraldehyde-3-P via aldolase (B); also interferes with phosphate levels globally

Front 30

What are two potential problems with galactose metabolism and which is more severe?

Back 30

classcial galactosemia is more severe and is caused by a problem with glactose-1-phosphate uridylyitransferase and the concomitant buildup of galactose-1-phosphate; nonclassical gaactosemia Is caused by the dysfunction of galactokinase and can lead to the buildup of galactose in the urine and potential cataracts

Front 31

What commonalities exist between hyperglycemic diabetics and galactose metabolism that can lead to cataracts?

Back 31

an aldol reductase converts the superabundance of sugar (due to a lack of functioning initial kinase) to sorbitol or galctitol which both aboserb water and can cause cataracts when the accumlate in the eye

Front 32

How is fructose formed in men?

Back 32

it's converted from sorbitol to D-fructose via sorbitol dehydrogenase

Front 33

How is lactose formed in a woman after childbirth?

Back 33

the hormone prolactin induces lactabumin wich increases the activity of galaltosyl transferase,allowing for the attachment of galctose to glucose