Respiration Flashcards
What is ATP broken down into?
ATP is broken down into ADP + Pi to release energy.
Can ADP + Pi be synthesised back into ATP?
Yes. Energy from the breakdown of glucose is used to synthesise ATP from ADP + Pi.
What are the four uses of energy in cells?
- muscle cell contraction
- cell division
- protein synthesis
- transmission of nerve impulses
What is meant by respiration?
Respiration is the release of chemical energy in an organism by a series of enzyme-controlled reactions.
What is the first stage of aerobic respiration?
glucose is broken down into 2x pyruvate which releases energy to make 2 ATP.
Does stage one of aerobic respiration need oxygen?
No
What does stage one of aerobic respiration take place?
Cytoplasm
What happens in stage two of aerobic respiration?
2x pyruvate + oxygen produces carbon dioxide + water + energy to make lots of ATP (specifically - 38)
Does stage two of aerobic respiration need oxygen?
Yes
Where does stage two of aerobic respiration occur?
Mitochondria
What does a cell do if there is no oxygen to move to stage two of aerobic respiration?
It does fermentation.
What is the process of fermentation in animal cells?
The 2x pyruvate is converted into lactate. Once oxygen debt is repaid, the reaction can reverse and then move to stage two of aerobic respiration.
What is the process of fermentation in plant and yeast cells?
2x pyruvate is converted into carbon dioxide + ethanol.
This reaction is irreversible because the carbon dioxide diffuses and so cannot be reused.
What is the test for carbon dioxide?
Lime water turns cloudy
Explain the process of the respirometer.
CO₂ is being absorbed by the potassium hydroxide at the bottom of the tube. The O₂ that is used up in the tube causes a pressure change. The change in pressure draws the dye up towards the organism.
Speed of dye = rate of respiration.
