Exam 1 Newest With Questions And
Answers 2026/2027 Graded A
What is the Endospore stain used for? - ANSWER>-is a structural stain that allows you to identify the presence and
location of spores in the form of endospores or free spores
-Schaeffer-Fulton Method discovered by Alice B. Schaeffer and Macdonald Fulton
-Spores are stained along with vegetative cells
Endospore Stain: Primary dye, Mordant(if applicable), decolorizer, and counterstain - ANSWER>-Primary Dye:
Malachite Green (stains all structure present including free spores, endospores, and vegetative cells
-Steaming: functions to force malachite green into the spores better
, -Decolorizer: Water (malachite green is water soluble and does not bind well to bacterial cells); spores will
remained stained, while vegetative will release stain and become colorless
-Secondary Dye: Safrinin (stains vegetative cells pink)
A pure culture is one that contains...? - ANSWER>A single bacterial species
Growth Medium - ANSWER>-can be selective or differential and are useful for isolating certain species of bacteria
-in all media there is carbon, nitrogen, inorganic phosphate and sulfur along with trace elements, water, and
vitamins
Agar - ANSWER>-a gelatin-like substance derived from the seaweed Gelidium
-first discovered in Japan
-Use of agar in lab is credited to Fanny Hesse