Biochem Test 3

Front 1

What are other names for Pentose Phosphate Pathway?

Back 1

Hexose Monophosphate Shunt
Phosphogluconate Pathway

Front 2

Is PPP aerobic or anaerobic?

Back 2

anaerobic

Front 3

what are the 2 major products of the PPP?

Back 3

ribose-5-phosphate, NADPH

Front 4

what is ribose-5-phosphate used for?

Back 4

nucleotide synthesis

Front 5

what is NADPH used for?

Back 5

biosynthetic reactions and antioxidant reducing power

Front 6

What does the oxidative phase produce?

Back 6

NADPH, ribose-5-phosphate

Front 7

What does the nonoxidative phase produce?

Back 7

converts 1 ribose-5-phosphate and 1-xylylose-5-phosphate and rearranges to glucose-6-phosphate

Front 8

when is the nonoxidative phase active?

Back 8

when NADPH is needed in high amounts

Front 9

Where does PPP occur in general?

Back 9

anywhere that requires lots of ribose-5-phosphate for new DNA synthesis

Front 10

what are specific examples of areas where PPP occurs?

Back 10

tissues that are rapidly dividing, like bone marrow, skin, intestinal mucosa, tumors

Front 11

Why do tumors use this pathway?

Back 11

requires only oxidative phase, tumor may outgrow its vasculature

Front 12

Where does PPP occur that requires both oxidative and nonoxidative phases?

Back 12

tissues synthesiing fatty acids, cholesterol, or steroid hormones
also tissues that are exposed to high levels of oxygen.

Front 13

what tissues are synthesizing fatty acids, cholesterol, or steroid hormones?

Back 13

liver, adipose, lactating mammary, adrenal cortex, gonads

Front 14

what tissues are exposed to high levels of oxygen?

Back 14

erythrocytes, cornea and lens.

Front 15

Which phases of PPP are required if ribose-5-phosphate is wanted?

Back 15

only oxidative phase

Front 16

Which phases are required if NADPH is wanted?

Back 16

nonoxidative

Front 17

what sugars are used and created in the nonoxidative phase of PPP?

Back 17

six 5-C sugars phosphates are converted to five 6-C sugar phosphates

Front 18

which enzyme takes ribulose-5-phosphate to glucose-6-phosphate?

Back 18

transketolase, transaldolase

Front 19

what is gluthathione (GSH)?

Back 19

a tripeptide comprised of Glu, Cys, & Gly

Front 20

What does GSH do?

Back 20

can serve as a proton donor to reduce proteins that have been oxidized.

Front 21

how many steps are involved in the oxidative phase of PPP?

Back 21

4 steps

Front 22

how many steps of the oxidative phase of PPP involve dehydrogenase?

Back 22

2

Front 23

what do the dehydrogenase steps of oxidative phase of PPP produce?

Back 23

NADPH

Front 24

what is the first step of oxidative phase of PPP?

Back 24

Glucose-6-phosphate to 6-phosphoglucono-gamma-lactone via glucose-6-phosphate dehydrogenase

Front 25

what is step 2 of the oxidative phase of PPP?

Back 25

6-phosphoglucono-gamma-lactone to 6 phosphogluconate via lactonase

Front 26

what is the 3rd step of the oxidative phase of PPP?

Back 26

6 phosphogluconate to D-ribulose-5-phosphate via 6-phosphogluconate dehydogenase

Front 27

what is the 4th step of the oxidative phase of PPP?

Back 27

D-ribulose-5-phosphate to D-ribose-phosphate via phophopentose isomerase

Front 28

what initiates the non-oxidative phase of PPP?

Back 28

xylulose-5-phosphate and ribose-5-phosphate

Front 29

what is step 1 of the nonoxidative phase of the PPP?

Back 29

ribulose-5-phosphate to xylulose-5-phosphate via ribose-5-phosphate epimerase

Front 30

what does xylulose-5-phosphate do in nonoxidative phase of PPP?

Back 30

activates protein phosphatase 2A, which activates FK2, which stimulates glycolysis

Front 31

which 2 enzymes transfer 2C or 3C ketose units to aldose acceptors in nonoxidative PPP?

Back 31

transketolase and transaldolase

Front 32

what cofactor in PPP is also a B vitamin?

Back 32

thiamine pyrophosphate cofactor (TPP)

Front 33

describe the transketolase reaction

Back 33

a 2 carbon ketose donor is transfered to an aldose acceptor via transketolase with TPP

Front 34

what disease is caused by a mutation in transketolase and severe deficiency in thiamine?

Back 34

Wernicke-Korsakoff syndrome

Front 35

In whom is Wernicke-Korsakoff syndrome most common?

Back 35

alcoholics due to poor intestinal absorption of the vitamin

Front 36

What are symptoms of Wernicke-Korsakoff syndrome?

Back 36

memory loss, confusion, and partial paralysis

Front 37

what is the second step in the nonoxidative phase of PPP?

Back 37

xylulose-5-phosphate + ribose-5-phosphate goes to glyceraldehyde-3-phosphate + sedoheptulose-7-phosphate via transketolase with TPP

Front 38

what is step 3 of the nonoxidative phase of PPP?

Back 38

transfer of 3 carbon ketose group to aldose acceptor via transaldolase

Front 39

which enzyme is stabilized by resonance and is a protonated schiff base?

Back 39

transaldolase

Front 40

what is the fourth step of nonoxidative phase in PPP?

Back 40

makes glyceraldehyde-3-hosphate and fructose-6-phosphate via transketolase and TPP

Front 41

how do high levels of NADPH affect G6PDH?

Back 41

high levels of NADPH inhibit G6PDH

Front 42

How do high levels of NADPH affect G6P?

Back 42

makes G6P available for glycolysis

Front 43

what are two reactive oxygen species that can damage cell membranes and cause hemolysis?

Back 43

O2 and H202

Front 44

how does PPP affect red blood cells?

Back 44

maintain high NADPH and GSH for repair of oxidative damage

Front 45

what disease is a deficiency in G6PDH?

Back 45

chemolytic anemia

Front 46

what is malaria caused by?

Back 46

a parasite transmitted by the anopheles mosquito

Front 47

what are the four strains of plasmodium that affect man and cause malaria?

Back 47

plasmodium falciparum
plasmodium malariae
plasmodium ovale
plasmodium vivax

Front 48

which is the most deadly plasmodium that causes malaria?

Back 48

plasmodium falciparum

Front 49

what are symptoms of uncomplicated malaria

Back 49

fever, chills, headache, muscle ache, vomiting, malaise

Front 50

what are symptoms of complicated malaria?

Back 50

cerebral malaria, severe anemia, kidney failure

Front 51

where is malaria on the world death list?

Back 51

4th leading cause of death in children worldwide

Front 52

what is the most common genetic enzymopathy?

Back 52

G6PDH deficiency

Front 53

how many variants of G6PDH deficiency are there?

Back 53

100

Front 54

how many people are affected globally by genetic enzymopathy?

Back 54

400 million

Front 55

what populations is G6PDH most common?

Back 55

african, mediterranean, asian

Front 56

what races are most affected?

Back 56

50% kurdish men
10-14% african american men
<0.1% northern europeans

Front 57

what is the genetic characterization of G6PDH defiiency deisease?

Back 57

x-linked recessive

Front 58

how are females affected in G6PDH deficiency disease?

Back 58

asymptomatic carriers

Front 59

how are males affected in G6PDH deficiency disease?

Back 59

hemizygous

Front 60

how does loss of G6PDH loss of functionality affect red blood cells?

Back 60

rbc become more susceptible to oxidative stress.

Front 61

what causes acute hemolysis in G6PDH deficiency?

Back 61

exposure to some chemicals induces hemolysis

Front 62

what chemicals cause hemolysis in G6PDH deficiency?

Back 62

primaquine (antimalarial)
sulfonamides (antibiotics)
aspirin/NSAIDs
Napthalene (moth balls)
fava beans

Front 63

what are symptoms of hemolytic anemia?

Back 63

dark urine (excretion of hemoglobin)
abdominal and back pain
jaundice (high bilirubin from catabolism of heme)
chronic forms: gallstones, enlarged spleen, cataracts

Front 64

who are famous victims of malaria?

Back 64

alexander the great, genghis khan, lord byron

Front 65

What are lipids?

Back 65

group of structurally and functionally diverse biomolecules that don't dissolve in watermade in living systems by biochemical reaction.