Pentose Phosphate Pathway

Question 1

3 pentose phosphates that pentose phosphate pathway synthesizes

Answer 1

Ribulose 5-phosphate
Ribose 5- phosphate
Xylulose 5-phosphate

Question 2

Oxidative stage

Answer 2

Glucose 6-phosphate -> ribulose 5-phosphate

Question 3

Non-oxidative stage

Answer 3

If NADPH and nucleotides are needed, ribulose 5-phosphate is converted to ribose 5-phosphate
If NADPH is needed more than ribose 5-phosphate, then pentose phosphates are converted to glycolytic intermediates

Question 4

of glucose 6-phosphate molecules needed to complete 1 cycle of the pentose phosphate pathway

Answer 4

3 glucose 6-phosphate molecules needed

Question 5

Isomerases

Answer 5

Convert ribulose 5-phosphate to xylulose 5-phosphate and ribose 5-phosphate

Question 6

Transketolases

Answer 6

Catalyze transfer of a two-carbon segment from a ketose phosphate to an aldose phosphate
Xylulose 5-phosphate + ribose 5-phosphate -> glyceraldehyde 3-phosphate and a sedoheptulose 7-phosphate (7-carbon compound)

Question 7

Transaldolases

Answer 7

Catalyze transfer of a 3-carbon segment from a ketose phosphate to an aldose phosphate
Sedoheptulose 7-phosphate + G3P -> erythrose 4-phosphate + fructose 6-phosphate