Cellular Respiration & Energy Systems Flashcards
What controls the metabolic pathways of respiration?
Enzymes
What is the substrate and products of glycolysis?
The breakdown of glucose to pyruvate
How many molecules of ATP are required during the energy investment phase?
2
What name is given to the addition of a phosphate to the glucose?
Phosphorylation
What name is given to the phase of glycolysis where more ATP is generated?
energy pay-off phase
How many molecules of ATP are generated during the energy pay-off phase?
4
What is the net gain of ATP during glycolysis?
2
Where in the cell does glycolysis take place?
Cytoplasm
What 2 things does the coenzyme NAD collect?
- hydrogen ions
2. high energy electrons
Name the enzyme that breaks off the hydrogen ions.
dehydrogenase enzymes
Where does the citric acid cycle take place?
matrix of the mitochondria
How many carbons are in a pyruvate molecule?
3
What is pyruvate broken down into?
acetyl group
What is added to the acetyl group?
coenzyme A
What is the name of the 4C molecule that joins with acetyl coA?
oxaloacetate
What is formed when oxaloacetate joins with acetyl coA?
citrate
Where does the electron transport chain take place?
inner membrane of the mitochondria
What are passed along the electron transport chain?
High energy electrons
As electrons flow along the electron transport chain energy is released. What is it used for?
To pump hydrogen ions across the membrane
Through which protein do hydrogen ions return to the matrix?
ATP synthase
What is synthesised by ATP synthase?
errr ATP
Name 2 things the returning hydrogen ions combine with as they move back into the matrix.
- low energy electrons
2. oxygen
What is the final hydrogen acceptor?
Oxygen
What is formed from the oxygen, low energy electrons and hydrogen ions?
Water
Every time a carbon molecule is lost during respiration, what is released?
carbon dioxide
During anaerobic conditions, what is pyruvate converted into in animal cells?
lactate
What role does NAD play in making lactate during anaerobic conditions?
It transfers hydrogen produced during glycolysis, adds it to the pyruvate to produce lactate.
What happens to muscles as lactate begins to accumulate?
Fatigue
Why is this described as a reversible reaction?
- Oxygen debt repaid when exercise complete
2. Respiration provides energy to convert the lactate back to pyruvate and glucose in the liver
Name the 2 types of skeletal muscle fibre.
- slow twitch
2. fast twitch
Describe the structure of slow twitch muscle fibres.
- Rely on aerobic respiration for ATP
- Many mitochondria
- Large blood supply
- High concentration of oxygen-storing protein myoglobin
- Major storage fuel is fats
Describe the structure of fast twitch fibres.
- Generate ATP through glycolysis
- Fewer mitochondria
- Lower blood supply
- Major storage fuel is glycogen
Activities linked to slow twitch muscle fibres?
Endurance - such as long distance running, cycling or cross country skiing
Activities linked to fast twitch muscle fibres?
Sprinting or weightlifting
Describe the contractions of slow twitch muscle fibres
Slow and can be sustained for longer
Describe the contractions of fast twitch muscle fibres
Contract quickly over shorter periods
What 3 things are produced from the breakdown of ATP?
ADP, Pi and Energy
State 3 things needed to phosphorylate ADP.
ADP (hello), Pi and Energy
