What are "CFUs?"

What are "CFUs?"

• A. Colony forming units
• B. Certified fermentation units
• C. Certified food units
• D. Colony fluorescent units

Answer: (A)

CFUs stands for Colony Forming Units, a way to quantify viable microorganisms in a sample. In microbiology, you plate a diluted sample on solid growth medium and incubate it; the colonies that appear are assumed to have arisen from individual viable cells (or small clumps) that were able to reproduce. By counting the colonies and accounting for the dilution, you estimate how many colony forming units were present per unit of sample. This measure reflects living, reproducing organisms, not just total cells. Other options don’t fit because they aren’t standard terms used to quantify viable microbes. “Certified fermentation units,” “Certified food units,” and “Colony fluorescent units” aren’t recognized metrics for microbial load or viability.

CFUs stands for Colony Forming Units, a way to quantify viable microorganisms in a sample. In microbiology, you plate a diluted sample on solid growth medium and incubate it; the colonies that appear are assumed to have arisen from individual viable cells (or small clumps) that were able to reproduce. By counting the colonies and accounting for the dilution, you estimate how many colony forming units were present per unit of sample. This measure reflects living, reproducing organisms, not just total cells.

Other options don’t fit because they aren’t standard terms used to quantify viable microbes. “Certified fermentation units,” “Certified food units,” and “Colony fluorescent units” aren’t recognized metrics for microbial load or viability.