Laboratory Exercise 5-4 Observations and interpretations 1. Using table 5-6, page 253, as a guide, record your results and interpretations in the table below. Organism | Bubbles? Y/N | +/- | Interpretation Uninoculated control (slant test only) | No bubbles | negative | Catalase is absent because is a slant test only. L. lactis | No bubbles | negative | Catalase is absent or not detectable. S. epidimidis | Bubbles | positive | Catalase is present. Questions 1. Think about the advice given in the procedure to tests a known catalase-positive organism along with an unknown. a. Is this a positive or a negative control? * The catalase-positive is a positive control because catalase is present. b. What information is provided by the results
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