Unit 1.7 - Electric Transport Chain

Question 1

Where does the electron transport chain occur?

Answer 1

The inner membrane of the mitochondria

Question 2

Where does glycolysis occur?

Answer 2

Cytoplasm

Question 3

Where does the citric acid cycle occur?

Answer 3

The matrix of the mitochondria

Question 4

What is glycolysis?

Answer 4

The breakdown of glucose to pyruvate in the cytoplasm?

Question 5

Describe the process of glycolysis

Answer 5

• ATP is required for the phosphorylation of glucose and intermediates during the energy investment phase
• This leads to the generation of more ATP during the Emery pay off stage and results in a net gain of ATP

Question 6

Describe the citric acid cycle

Answer 6

• In aerobic conditions pyruvate is broken down to an acetyl group that combines with conenzyme A forming acetyl coenzyme A
• The acetyl group form acetyl coenzyme A combines with oxaloactate to down citrate
• During a series of enzyme controlled steps, citrate is gradually converted back into oxaloacetate which results in the generation of ATP and release of carbon dioxide

Question 7

What are the end products of the electron transport chain?

Answer 7

Water and ATP

Question 8

Explain the role of dehydrogenase enzymes

Answer 8

• They remove hydrogen ions and electrons and pass them to the coenzyme NAD, forming NADH
• This occurs in both glycolysis and the citric acid cycle
• The hydrogen ions and electrons from NADH are passed to the electron transport chain on the inner mitochondrial membrane

Question 9

What’s the role of ATP in the transfer of energy?

Answer 9

ATP is used to transfer energy to cellular processes which require energy

Question 10

Describe the events that occur during the electrons transport chain

Answer 10

• The electron transport chain is a series of carrier proteins found on the inner mitochondrial membrane
• NADH release the hydrogen ions and electrons into the electron transport chain
• The electrons pass along the chain of electron receptors, releasing energy
• The energy is used to pump H ions across the inner mitochondrial membrane
• The flow of these ions back through the membrane protein ATP synthesis results in the synthesis of ATP
• The oxygen combines with hydrogen ions and electrons to form water