Heat from Fungal Respiration Requires Cooling

Steps:

• Fermentation grows fungi on glucose for single cell protein, involving aerobic respiration.
• Respiration breaks down substrates, releasing energy as heat (exothermic reaction).
• Excess heat raises temperature, inhibiting fungal growth and protein yield.
• Cooling unit removes heat to maintain optimal temperature (around 25-30°C for fungi).

Why D is correct:

• Respiration is exothermic, converting chemical energy to heat via ATP production (Q = ΔH < 0 in biochemical reactions).

Why the others are wrong:

• A: Fungi grow optimally at moderate temperatures, not lower; cooling prevents overheating, not to lower temperature.
• B: Glucose syrup addition temperature is controlled, not a primary heat source.
• C: Air bubbles aid aeration but do not generate heat; friction from mixing is minor.

Final answer: D