Big Picture
What molecule provides the chemical energy that begins the process of cellular respiration?
glucose
In what part of the cell does glycolysis occur?
cytoplasm
Where does the Krebs cycle take place in a eukaryotic cell?
Mitochondrial matrix
What molecule is formed when oxygen accepts electrons and hydrogen ions at the end of the ETC?
water
Why is glycolysis considered an anaerobic process?
Because it does not require oxygen
What is the primary energy-carrying molecule that cells produce during cellular respiration?
ATP
What two molecules are produced when one glucose molecule is split during glycolysis?
Two pyruvate molecules
Which waste gas is released during the Krebs cycle?
carbon dioxide
Where is the electron transport chain located within the mitochondria? (be specific)
Inner mitochondrial membrane
If you are performing anaerobic respiration, what steps of cellular respiration are you not performing?
Krebs Cycle and ETC
plus pyruvate oxidation!
How are photosynthesis and cellular respiration connected?
The products of one are the reactants of the other
What type of fermentation do yeast cells perform when oxygen is absent?
Alcoholic fermentation
What molecules store most of the energy captured during the Krebs cycle?
NADH and FADH₂
Which molecule acts as the final electron acceptor in the electron transport chain?
Oxygen
Why are NADH and FADH₂ considered high-energy molecules?
Because they carry high-energy electrons
How does the folded structure of the inner mitochondrial membrane increase ATP production?
By increasing surface area for the electron transport chain
Why does glycolysis alone produce only a small amount of ATP, even though high energy glucose is broken down?
Because most of the energy remains stored in pyruvate and electron carriers
What molecule enters the Krebs cycle after pyruvate is modified?
Acetyl-CoA
What protein in the ETC is inhibited by cyanide?
cytochrome C
Why is carbon dioxide considered a waste product of cellular respiration?
Because it contains carbon that is no longer useful for energy extraction and is not used in any step of cellular respiration
Why did leaf disks float during our past photosynthesis experiment?
Oxygen produced during photosynthesis accumulates in the leaf air spaces
What is the primary role of fermentation in cells?
To regenerate NAD⁺ so glycolysis can continue
What would happen to ATP production if enzymes in the Krebs cycle were denatured?
ATP production would decrease or stop because the reactions could not proceed
What is the name for the process that uses the proton gradient to produce ATP in the mitochondria?
(1000 points if you answer the first question!)
OR: What is the name for the protein the protons flow through to generate ATP?
chemiosmosis
ATP Synthase
Why do muscle cells switch to fermentation during intense exercise, and what type of fermentation do they perform?
Because oxygen delivery cannot meet demand for aerobic respiration
Lactic acid fermentation