Microbiology LAB Final Exam LSUE Exam Questions With 100% Correct Answers.

Cotton plugs or screw caps are used in test tubes containing sterile media or pure cultures to - a. Prevent unfiltered air or dust particles from entering the tubes, maintain anaerobic conditions and prevent the culture from spilling The pH indicator in Simmon's citrate agar is what? - a. Bromthymol Blue Bacteria that show no preference, grow equally well in aerobic or anaerobic conditions are - a. Facultative The protein that DOES NOT give milk its white color is - a. Albumin Beef extract is a source of - Salt, Vitamins, Carbohydrates Bacteria which grow in the dark & in media composed mainly of organic compounds are - Heterotrophic Media that allows one type of bacteria to grow on them while preventing growth of other types of bacteria is called - Selective media If the pH of the medium is higher than 6.8 you can adjust to 6.8 by - Adding drops of HCL to lower it