ETIABO: Respiration- Link reaction

Question 1

What are we left with at the end of glycolysis?

Answer 1

Two pyruvate molecules

Question 2

Where does the link reaction take place?

Answer 2

Mitochondrial matrix

Question 3

In the link reaction, the 2 pyruvate molecules move from the cytoplasm to the ______ ______ via active transport.

Answer 3

Mitochondrial matrix.

Question 4

By what process does pyruvate move from the cytoplasm to the mitochondrial matrix?

Answer 4

Active transport

Question 5

What is the shortened name for acetylcoenzyme A?

Answer 5

Acetyl-CoA

Question 6

After glycolysis pyruvate is _____ _______ into the mitochondrial matrix.

Answer 6

Actively transported

Question 7

Name the products produced in the link reaction:

Answer 7

Pyruvate —> Acetate —-> Acetylcoenzyme A

Question 8

In the conversion of pyrivate to acetate, a hydrogen molecule is lost (oxidised). What happens to this H+ molecule?

Answer 8

Added to NAD to form NADH (reduced NAD)

Question 9

Explain how pyruvate is converted into acetate:

Answer 9

• Pyruvate looses a carbon molecule in the form of carbon dioxide (which is then removed when we exhale).
• Pyruvate looses a hydrogen molecule- which is then added to NAD (pyruvate is oxidised).
• Acetate is formed.

Question 10

NAD is a _______.

Answer 10

Coenzyme

Question 11

Explain how acetate is converted into acetylcoenzyme A.

Answer 11

• Acetate has coenzyme A added to it.
• Forms acetylcoenzyme A

Question 12

Explain what happens in the link reaction:

Answer 12

• After glycolysis pyruvate is transported from the cytoplasm to the mitochondrial matrix via active transport.
• Pyruvate looses a carbon molecule in the form of carbon dioxide, and a hydrogen molecule (which is added to NAD to form NADH)
• Acetate is formed.
• Acetate has coenzyme A added to it.
• Acetylcoenzyme A is formed.