Electron Transport Chain
Where does the electron transport chain occur in the mitochondria?
Inner mitochondrial membrane.
What enzyme makes ATP during cellular respiration?
ATP synthase.
What is ATP used for?
The main energy source for cellular activities.
Besides glucose, what other molecules can cells use for energy?
Fats and proteins.
What is the overall purpose of cellular respiration?
To convert energy stored in food into ATP.
What happens as electrons move through the electron transport chain?
Energy is released and used to help produce ATP.
Where is ATP synthase located?
Inner mitochondrial membrane.
Approximately how many ATP molecules can be produced from one glucose molecule?
About 36–38 ATP.
Why can fats produce more ATP than glucose?
Fatty acids have longer carbon chains, providing more energy.
What molecule stores usable energy for the cell?
ATP.
What type of electrons enter the electron transport chain?
High-energy electrons.
What gradient powers ATP synthase?
A hydrogen ion (H⁺) gradient.
What percentage of glucose energy is captured as ATP?
About 40%.
What happens to extra food energy?
It can be converted into fat for storage.
What role does oxygen play in cellular respiration?
It acts as the final electron acceptor in the electron transport chain.
What is the final electron acceptor in the electron transport chain?
Oxygen.
Why are H⁺ ions pumped into the intermembrane space?
To create a concentration gradient that stores energy.
What happens to the remaining energy from glucose?
It is released as heat
Why can proteins be used in metabolism?
They can be broken down into molecules that enter energy-producing pathways.
Why is the electron transport chain important?
It creates the H⁺ gradient needed for ATP production.
What is produced when oxygen accepts electrons?
Water (H₂O).
Explain how ATP synthase produces ATP.
H⁺ ions flow through ATP synthase, and the energy from that movement is used to combine ADP and phosphate to make ATP.
Why might different cells produce different amounts of ATP?
Different cells have different efficiencies and conditions, causing some to produce less than the maximum.
Why might cells use different energy sources?
Cells use available nutrients to produce energy and materials needed for survival.
Explain the pathway:
Glucose → Electron Transport Chain → ATP
Energy from glucose is transferred through electron carriers, creating an H⁺ gradient that powers ATP synthase to produce ATP.