ASCP Technologist in Microbiology (M) Complete Practice Exam 2025

The use of Thayer Martin VCN media is specifically designed to isolate Neisseria gonorrhoeae from clinical samples. This selective media contains antibiotics that inhibit the growth of competing normal flora in clinical specimens, such as those obtained from the urogenital tract. Thayer Martin media is enriched and specifically tailored to favor the growth of Neisseria gonorrhoeae while suppressing other organisms, making it the most effective choice when seeking to culture this pathogen.

The other media listed do not provide the same level of selectivity. Blood agar is a general-purpose medium that supports a wide range of bacteria but does not inhibit competing flora, which can lead to mixed cultures. Chocolate agar, while enriched and suitable for many fastidious organisms, does not possess the necessary selective antibiotics to isolate Neisseria gonorrhoeae from other bacteria. MacConkey agar is selective for Gram-negative bacteria, particularly enteric bacteria, and is not suitable for Neisseria species, as it does not contain the specific inhibitors needed to suppress competing flora and does not create the ideal growth conditions for Neisseria gonorrhoeae.