Key Area 2.2 Cell respiration Flashcards
What does respiration generate?
ATP
What is ATP made of?
An adenine molecule with three phosphate groups attached.
What is the first stage of aerobic respiration called?
Glycolysis.
Where does glycolysis take place?
Cytoplasm.
What is glucose broken down too?
Intermediates and finally pyruvate.
What is part one of glycolysis called?
Energy investment stage.
Why is step 1 called the energy investment stage?
Because 2 ATP are needed for the phosphorylation of intermediates.
What is step 2 in glycolysis called?
Energy gain.
Why is step 2 called the energy gain stage?
4 ATP are generated.
Why is it said that there is a net gain of 2 ATP?
2 ATP are used but 4 are made so overall there is a gain of 2 ATP.
What enzyme is used in glycolysis?
Dehydrogenase enzyme.
What does the dehydrogenase enzyme do?
Removes hydrogen ions and electrons from intermediates.
What picks up hydrogen ions and electrons in glycolysis?
NAD
What does NAD turn into when it accepts hydrogen ions and electrons?
NADH
Where does NADH carry the hydrogen ions and electrons to?
The electron transport chain.
What is stage 2 of aerobic respiration called?
The citric acid cycle.
What must be present for the citric acid cycle to start?
Oxygen.
Where does the citric acid cycle take place?
Central matrix of the mitochondria.
What is pyruvate broken down into?
An acetyl group.
What does the acetyl group bind with? What does this form?
Coenzyme A. Acytyle Coenzyme A
What is released from the ECS?
CO2 and Hydrogen.
What does the acetyl from acetyl coenzyme A combine with? What does it form?
Oxaloacetate. Citrate
What does hydrogen ions and electrons combine with? What does this form?
NAD to form NADH.
How many ATP are produced from the citric acid cycle?
1
What happens to oxaloacetate?
It is regenerated for continuation of the cycle.
What is stage 3 of aerobic respiration called?
The electron transport chain (ECS).
Where does ECS take place?
Inner membrane of the mitochondria.
What does the NADH do?
Passes electrons to the electron transport system.
What do the electrons then do?
Flow along the electron transport system and release energy.
What is this energy used for?
To pump hydrogen ions across the mitochondrial membrane and into the inner membrane.
What does hydrogen move through?
ATP synthase.
What does ATP synthase do?
Makes ATP.
What is oxygen?
The final hydrogen ion and electron acceptor.
What does the oxygen form when it accepts the hydrogen ions and electrons?
Water.
What is fermentation?
Respiration which takes place in the absence of oxygen.
When does fermentation occur in animals?
During strenuous exercise.
What is pyruvate converted into during fermentation in animals?
Lactate.
Is fermentation in animals reversible?
Yes.
Is fermentation is plants reversible?
No.
Why is fermentation is plants irreversible?
The cells become damaged due to the products of fermentation.
What are the products of fermentation in plants?
Ethanol and CO2
