MIC 205 Final questions with correct answers

Haemophilus influenzae is a Gram-negative coccobacillus. If you looked at a Gram-stained culture using a light microscope, you would expect to see CORRECT ANSWER • pink, very short rods. If the decimal reduction time is 1 minute, how many minutes would it take to kill all organisms when starting with 100,000 organisms? CORRECT ANSWER 6 A research laboratory is investigating environmental factors that would inhibit the growth of Archaea. One question they have is if adding the antibiotic penicillin would be effective in controlling their growth. What do you think the outcome would be if they tried this? CORRECT ANSWER • The penicillin wouldn't affect the Archaea because it prevents crosslinking of peptidoglycan-Archaea don't have this compound in their cell walls. You are performing a Gram stain on gram-negative bacteria, and you forgot the Safranin stain step. When you look at the stained specimen, what do you see? CORRECT ANSWER colorless Place the steps of the Gram stain in the correct order: Alcohol-acetone Safranin Crystal violet Iodine CORRECT ANSWER 3 Alcohol aceton