Glucose Metabolism (GLYCOLYSIS)

Question 1

How many carbons do these molecules have?

Glucose
pyruvate
acetyl-CoA

Answer 1

glucose = 6
pyruvate = 3
acetyl-CoA = 2

Question 2

What is the overall goal?

Answer 2

full oxidation of glucose (4CO2 + 4H2O)

Question 3

What are the 4 ways glucose can be used?

Answer 3

1. storage (glycogen, starch, sucrose)
2. oxidation via glycolysis (Pyruvate + ATP + NADH)
3. oxidation via pentose phosphate pathway (ribose 5-phosphate + NADPH –> nucleotide synthesis and fatty acid synthesis)
4. synthesis of structural polymers (cellulose)

Question 4

What came first: photosynthesis or glycolysis?

Answer 4

glycolysis

Question 5

How did early organisms extract free energy from glucose anaerobically?

Answer 5

1: Activate it by phosphorylation (put some money in the bank – initial investment)

#2: Collect energy from the high-energy metabolites (collect that interest from the bank)

Question 6

What is the summary of glycolysis?

What is used?

What is made?

What are the net products?

Answer 6

USED:
1 glucose
2 ATP
2 NAD+

MADE:
2 pyruvate
4 ATP
2 NADH

NET:
2 pyruvate
2 ATP
2 NADH

Question 7

Stage 0 = ?
Stage 1 = ?
Stage 2 = ?

Answer 7

Stage 0 = bring glucose into the cell
Stage 1 = the investment stage
Stage 2 = the payoff stage

Question 9

Glucose transporters are what kind of transporter?

Answer 9

facilitated uniporters (largely insilin dependent)

Question 10

What happens if GLUT4 no longer responds in the Stage 0?

Answer 10

we lose the ability to transport glucose into the cell

Question 11

What happens in the “investment stage”?

Answer 11

consume 2 ATP

hexose carbon chains are converted to glyceraldehyde 3 -phosphate (2 x 3 carbon molecule)

Question 12

What is generated in the “payoff stage”? What is “net”?

Answer 12

Generates:
4 ATP
2 NADH
2 pyruvate

NET (payoff investment):
2 ATP
2 NADH
2 pyruvate