Unit 2 - Cellular Respiration Flashcards
What is glycolysis?
Glycolysis is the breakdown of glucose to pyruvate in the cytoplasm.
What happens in both stages of glycolysis?
And what happens if oxygen is present
Stage 1: Glucose and intermediates is phosphorylized by use of 2 ATP (Energy investment stage)
Stage 2: Once glucose is converted into pyruvate 4 ATP is made, = 2 ATP net gain
•In aerobic conditions pyruvate is broken down
to an acetyl group that combines with coenzyme A forming acetyl coenzyme A.
Where does the citric acid cycle occur?
In the matrix of the mitochondria ( can only occur if oxygen is present)
What happens in the citric acid cycle?
- Acetyl group from “acetyl coenzyme A” combines with oxalocetate to form citrate
- During a series of enzyme controlled steps, citrate is converted back into oxaloacetate
- Cycle generates ATP and gives off CO2
What do dehydrogenase enzymes do?
- Remove hydrogen ions and electrons from both glycolysis and citric acid cycle and passes them to the coenzyme NAD forming NADH
- Hydrogen ions and electrons from NADH then passed into the electron transport chain
What is the electron transport chain?
A series of carrier proteins attached to the inner mitochondrial membrane
What happens in the electron transport chain?
- NADH passes it’s hydrogen ions and electrons down a series of electron acceptors thus releasing energy WHICH is used to pump hydrogen ions across the inner membrane by ACTIVE TRANSPORT
- Return flow of hydrogen ions by diffusion via membrane protein
- ATP synthase drives the synthesis of the bulk of the ATP produced in respiration
- Final electron acceptor is oxygen which combines with hydrogen ions and electrons to form water
What is ATP?
High energy compound which transfers energy
How is ATP produced?
When ADP combines with phosphate in phosphorylation, building up energy and releasing when broken down into ADP and phosphate once more
