Question

which is required for both anaerobic respiration and aerobic respiration?
oxygen
water
mitochondria
glucose

Explanation:

• Oxygen: Anaerobic respiration does not require oxygen. Aerobic respiration does. So oxygen is not a common requirement.
• Water: Anaerobic respiration (e.g., in some bacteria or during lactic acid fermentation in animals) does not produce water as a major by - product in the same way aerobic respiration (where \(C_6H_{12}O_6+6O_2

ightarrow6CO_2 + 6H_2O+\text{energy}\)) does.

• Mitochondria: Anaerobic respiration (such as glycolysis which can occur in the cytoplasm of prokaryotes or in the cytoplasm of eukaryotes before further anaerobic steps) does not require mitochondria. Aerobic respiration (the Krebs cycle and electron transport chain, which occur in mitochondria in eukaryotes) requires mitochondria.
• Glucose: Both aerobic respiration (\(C_6H_{12}O_6+6O_2

ightarrow6CO_2 + 6H_2O+\text{energy}\)) and anaerobic respiration (e.g., \(C_6H_{12}O_6
ightarrow2C_2H_5OH + 2CO_2+\text{energy}\) in alcoholic fermentation or \(C_6H_{12}O_6
ightarrow2C_3H_6O_3+\text{energy}\) in lactic acid fermentation) start with glucose as the primary substrate for energy production.

Answer:

glucose