Question

why do humans need oxygen to survive?
without enough oxygen, humans perform fermentation, an anaerobic process that does not produce enough atp for humans to maintain homeostasis.
without oxygen, our bodies cannot combust methane (ch₄) to produce co₂ and h₂o needed to produce heat so that the organisms can maintain thermal homeostasis.
oxygen helps us breathe.
oxygen is used during fermentation to keep glycolysis going, allowing anaerobic respiration to produce lactic acid.

Explanation:

• Analyze Option 1: Humans use aerobic respiration (needing O₂) to make most ATP. Without enough O₂, they ferment (anaerobic), which makes little ATP—insufficient for homeostasis. This matches O₂’s role in ATP production.
• Analyze Option 2: Humans don’t combust methane; they metabolize glucose. So this is incorrect.
• Analyze Option 3: “Oxygen helps us breathe” is a vague description, not the core reason (O₂ is for ATP production, not just “helping breathe”).
• Analyze Option 4: Fermentation is anaerobic (no O₂ used). So this statement is wrong.

Answer:

A. Without enough oxygen, humans perform fermentation, an anaerobic process that does not produce enough ATP for humans to maintain homeostasis.