2.2 cellular respiration

Question 1

What is glycolysis?

Answer 1

the breakdown of glucose to pyruvate in the cytoplasm

Question 2

What is the process of glycolysis?

Answer 2

• glucose is broken down into intermediate products
• 2 ATP phosphorylises glucose and intermediates during the energy investment stage
• intermediate products are broken down into pyruvate
• 4 ATP is generated in the energy pay-off stage
• net gain of 2ATP
• during the energy payoff stage dehydrogenase enzymes removes H+ ions and electrons whish combine with coenzyme NAD to form NADH
• if oxygen is present NADH transports hydrogen ions and electrons to the electron transport chain

Question 3

What is the process of the citric acid cycle?

Answer 3

• in aerobic conditions, pyruvate is broken down into an acetyl group and carbon dioxide is released
• acetyl group combines with coenzyme A
• forming acetyl coenzyme A
• acetyl group from acetyl coenzyme A combines with oxaloacetate
• to form citrate
• during a series of enzyme-controlled steps, citrate is gradually converted back into oxaloacetate
• resulting in the generation of ATP and release of carbon dioxide and NADH
• NADH transports hydrogen ions and electrons to the electron transport chain

Question 4

Where does the citric acid cycle happen?

Answer 4

the matrix of the mitochondria

Question 5

What is the role of dehydrogenase enzymes?

Answer 5

-remove hydrogen ions and electrons and pass them to coenzyme NAD, forming NADH. this happens in glycolysis and the citric acid cycle

Question 6

What happens to the hydrogen ions and electrons from NADH

Answer 6

• they are passed to the electron transport chain

- the electrons create the energy to pump hydrogen ions through the membrane and ATP synthase producing ATP

Question 7

What is a description of the electron transport chain?

Answer 7

• electrons (from NADH) are passed across the electron transport chain from releasing energy
• this energy allows hydrogen ions (from NADH) to be pumped across the inner mitochondrial membrane
• the flow of these ions back through the membrane protein ATP synthase results in the production of ATP
• hydrogen ions and electrons combine with oxygen to form water

Question 8

What is the electron transport chain?

Answer 8

-a series of carrier proteins attached to the inner mitochondrial membrane

Question 9

How is ATP generated?

Answer 9

ADP + Pi using the energy from respiration

Question 10

What is glycolysis and where does it take place?

Answer 10

a series of enzyme controlled reactions that happens in the cytoplasm of the cell

Question 11

What are the products of fermentation in plant and animal cells?

Answer 11

• animal-lactate-reversible reaction

- plant-ethanol and carbon dioxide

Question 12

What is the role of ATP?

Answer 12

to transfer energy to cellular processes that require energy

Question 13

What does phosphorylation in the energy investment phase of glycolysis result in?

Answer 13

the generation of more ATP in the energy payoff phase