Which description best fits mold growth on food?

• A. Contains hyphae, threadlike filaments, can be seen on foods, needs organic matter to grow, and is aerobic.
• B. Requires no oxygen and grows only in anaerobic environments.
• C. Is always easy to see without magnification.
• D. Grows only on metal surfaces.

Answer: (A)

Mold growth on food is best described by its hyphae—threadlike filaments that form a network, which you can often see as a fuzzy or powdery growth on the surface. Molds feed on organic matter, so they need something like food to grow, and they typically require oxygen, making them aerobic. This combination—filamentous hyphae, visible growth on organic substrates, and an oxygen-dependent growth process—fits what you’d expect from mold on food.

The other ideas don’t fit as well. Some molds aren’t completely anaerobic, and early mold growth can be microscopic, so it’s not always easy to see without magnification. Molds don’t grow only on metal surfaces; they commonly grow on many organic foods and other substrates.