2.8 Cell Respiration

Question 1

What is cell respiration?

Answer 1

the controlled release of energy from organic compounds to produce ATP

Question 2

What is ATP?

Answer 2

• universal energy molecule
• ADP is the empty energy carrier, when an extra phosphate is added it becomes ATP, this extra phosphate has a high energy phosphate bond and it is the breaking of this bond which is the energy

Question 3

Word equation for cell respiration

Answer 3

glucose + oxygen —–> carbon dioxide + water + ATP

Question 4

Aerobic respiration (SL)

Answer 4

C6H12O6 + 6O2 —–> 6CO2 + 6H2O + 38ATP

• requires oxygen
• gives large yield of ATP
• takes place in most organisms and cells
• 3 steps: glycolysis, Krebs Cycle and electron transport chain
• takes place in cytoplasm and mitochondria (matrix and cristae)
• when glucose is in short supply other molecules such as fats and proteins may be used

Question 5

Factors that affect rate of respiration

Answer 5

• amount of glucose
• amount of oxygen
• enzyme efficiency may be affected by temp, pH, poisons etc.
• the cells demand for energy