Harvesting Basics
Organisms that live on organic compounds produced by others are known as:
A. Autotrophs
B. Heterotrophs
C. Methanogens
D. Saprotrophs
B. Heterotrophs
In eukaryotes, pyruvate oxidation takes place in the:
A. Cytoplasm
B. Intermembrane space
C. Mitochondrial matrix
D. Inner membrane
C. Mitochondrial matrix
The Electron Transport Chain (ETC) is located in the:
A. Outer mitochondrial membrane
B. Inner mitochondrial membrane
C. Mitochondrial matrix
D. Cytoplasm
B. Inner mitochondrial membrane
The primary goal of fermentation is to recycle NADH back into:
A. Pyruvate
B. ATP
C. NAD+
D. Ethanol
C. NAD+
This molecule acts as a "low-energy" sensor and stimulates PFK activity:
A. ATP
B. Citrate
C. AMP
D. NADH
C. AMP
Glycolysis occurs in this specific part of the cell:
A. Mitochondrial matrix
B. Inner membrane
C. Cytoplasm
D. Nucleus
C. Cytoplasm
During pyruvate oxidation, the removal of a carboxyl group as CO2 is called:
A. Phosphorylation
B. Decarboxylation
C. Hydrogenation
D. Hydrolysis
B. Decarboxylation
In aerobic respiration, the final electron acceptor at the end of the ETC is:
A. NAD+
B. Pyruvate
C. Oxygen
D. Water
C. Oxygen
During intense exercise, animal muscle cells perform fermentation to produce:
A. Ethanol
B. Lactate
C. Acetaldehyde
D. Methane
B. Lactate
Before proteins can be used for energy, amino acids must undergo:
A. Phosphorylation
B. Deamination
C. Beta-oxidation
D. Fermentation
B. Deamination
Which enzyme is responsible for the first step of glycolysis (phosphorylating glucose):
A. Phosphofructokinase
B. Pyruvate kinase
C. Hexokinase
D. Isocitrate dehydrogenase
C. Hexokinase
For every turn of the Citric Acid Cycle, how many NADH molecules are produced?
A. 1
B. 2
C. 3
D. 6
C. 3
The drug Cyanide is deadly because it inhibits this specific complex in the ETC:
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
D. Complex IV
In yeast fermentation, CO2 is removed from pyruvate to first produce:
A. Ethanol
B. Lactate
C. Acetaldehyde
D. Oxaloacetate
C. Acetaldehyde
Fatty acids are converted into acetyl groups to enter the Citric Acid Cycle via:
A. Glycolysis
B. Decarboxylation
C. Beta-oxidation
D. Deamination
C. Beta-oxidation
The net energy yield from one molecule of glucose during glycolysis is:
A. 4 ATP and 2 NADH
B. 2 ATP and 0 NADH
C. 2 ATP and 2 NADH
D. 30 ATP and 10 NADH
C. 2 ATP and 2 NADH
The 2-carbon Acetyl-CoA combines with this 4-carbon molecule to start the Citric Acid Cycle:
A. Citrate
B. Malate
C. Oxaloacetate
D. Succinate
C. Oxaloacetate
Which energy-dense form of potential energy is used directly by ATP synthase?
A. High-energy electrons
B. A proton (H+) gradient
C. CO2 release
D. Heat energy
B. A proton (H+) gradient
Anaerobic respiration uses these as final electron acceptors instead of oxygen:
A. Organic molecules
B. Inorganic molecules (e.g., Nitrate, Sulfate)
C. ATP
D. Glucose
B. Inorganic molecules (e.g., Nitrate, Sulfate)
Phosphofructokinase (PFK) is allosterically inhibited by high levels of:
A. AMP and ADP
B. Oxygen and Water
C. ATP and Citrate
D. Pyruvate and Acetyl-CoA
C. ATP and Citrate
At the end of glycolysis, most of the original energy from glucose is still stored in:
A. ATP
B. NADH
C. Pyruvate
D. Water
C. Pyruvate
The Citric Acid Cycle is called a "metabolic hub" primarily because it:
A. Produces the most ATP directly
B. Is the only stage that uses oxygen
C. Provides intermediates for biosynthetic pathways
D. Occurs in the center of the cell
C. Provides intermediates for biosynthetic pathways
The theoretical ATP yield for eukaryotes from one glucose molecule is:
A. 2 ATP
B. 30 ATP
C. 32 ATP
D. 38 ATP
B. 30 ATP
Organisms that reduce CO2 to CH4 (methane) are called:
A. Sulfur prokaryotes
B. Heterotrophs
C. Methanogens
D. Yeasts
C. Methanogens
Which fuel source do cells preferentially use first for energy?
A. Lipids
B. Proteins
C. Glucose
D. Nucleic acids
C. Glucose