Link Reaction

Question 1

Where does link reaction occur?

Answer 1

• Mitochondrial matrix

Question 2

Another name for the link reaction?

Answer 2

Oxidative decarboxylation

Question 3

What is the purpose of the link reaction / oxidative decaroxylation?

Answer 3

Connects glycolysis and Krebs cycle

Question 4

Steps in link reaction summary?

Answer 4

1. Active transport of pyruvate
2. Decarboxylation
3. Removal of CO2
4. Oxidation of pyruvate
5. Reduction of NAD
6. Formation of acetyl CoA

Question 5

Active transport of pyruvate:

Answer 5

• Pyruvate from glycolysis
• Actively transported into the mitochondrial matrix
• Transported by specific carrier proteins

Question 6

Decarboxylation:

Answer 6

• In mitochondrial matrix
• Each pyruvate molecule is decarboxylated
• Lose one CO2 molecules

Question 7

Removal of CO2

Answer 7

• CO2 diffuses out of the mitochondria as a waste product

Question 8

Oxidation of pyruvate:

Answer 8

• Two hydrogen atoms are removed from pyruvate
• Pyruvate forms a two-carbon molecule (acetate)

Question 9

Reduction of NAD:

Answer 9

• Hydrogen atoms are used to reduce the coenzyme NAD
• Form reduced NAD (electron carrier)

Question 10

Formation of acetyl CoA:

Answer 10

• Acetate binds to coenzyme A
• Forms acetyl coenzyme A (acetyl CoA)

Question 11

Reactants:

Answer 11

• Pyruvate
• NAD
• Coenzyme A

Question 12

Products of link reaction

Answer 12

• Acetyl coenzyme A
• Reduced NAD
• Carbon dioxide

Question 13

How does pyruvate enter the matrix?

Answer 13

Symport(er)