Cellular Respiration Flashcards
(14 cards)
What does respiration involve?
Where does the energy from food end up being transferred to?
A series of enzyme controlled metabolic reactions which releases the chemical energy in food
A high energy compound called ATP
How is ATP made(structure)?
Does this process require energy?
By joining ADP with a single inorganic phosphate(Pi) molecule
To join these molecules together requires energy that can come from food(glucose)
What is ATP used for?
To transfer energy to cellular processes which require energy
Example- protein synthesis, DNA replication
How does phosphorylation occur?
What does it to a molecule?
When a phosphate group(from the breakdown of ATP) is added to a molecule
This addition makes the molecule more reactive
What is glycolysis?
The breakdown of glucose to pyruvate in the cytoplasm
What is the energy investment phase?
ATP is required for the phosphorylation of glucose and intermediates(during energy investment phase)
What is the energy pay off stage?
This leads to the generation of more ATP during the energy pay off stage and results in a net gain of ATP(2)
What do dehydrogenase enzymes do?
They remove hydrogen ions and electrons and pass them to the coenzyme NAD forming NADH
These hydrogen ions and electrons are later transported and used in the electron transport chain
What happens when O2 is present and not present after glycolysis?
Present- move on to citric acid cycle
Not present- undergo fermentation
Where does the citric acid cycle occur?
Matrix of the mitochondria
What is the pyruvate broken down into?
In aerobic conditions(O2 present) the pyruvate is broken down to an acetyl group(by losing carbon) that combines with coenzyme A to form acetyl coenzyme A
What happens in the citric acid cycle?
The acetyl group from the 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 CO2
The hydrogen ions and electrons are removed from substrates by the dehydrogenase enzyme and passed to NAD to form NADH
What is the electron transport chain?
A series of carrier proteins attached to the inner mitochondrial membrane
What are the 5 stages of the electron transport chain?
1) ATP synthesis- NADH released the electrons from the glycolysis and citric acid cycle, these electrons are then passed along the electron transport chain releasing energy
2) This energy allows hydrogen ions to be pumped across the inner mitochondrial membrane by the carrier proteins
3) The hydrogen ions then have a higher concentration on one side of the membrane the ions then naturally flow back through the membrane from a high concentration to a low concentration(diffusion) through a membrane protein called ATP synthase, resulting in the production of ATP
4) Finally, hydrogen ions and electrons combine with oxygen to form water
