Discussion Week 1 Study Guide Rated A+

why do some bacteria appear purple after being Gram stained while other appear pink? {Ans: Gram neg cells have few layers of peptidoglycan cell wall and an outer lipopolysaccharide membrane. Gram positive organism have several layers of pepitdoglycan and no outer membrane. The multiple layers of peptidoglycan retain the crystal violet -iodine complex so appear purple. Gram neg cells do not retain the crystal violet because there are few layers of peptidoglycan and the outer membrane is disrupted by the decolorizer}Resolution is the smallest distance by which 2 objects can be _________ and still be _________ a)magnified; seen b) separated; distinguished c) magnified; separated d) distinguished; separated e) magnified; distinguished {Ans: b) separated; distinguished}Antony van Leeuwenhoek is often referred to as the father of microbio. However many historians feel that Louis Pasteur, Robert Koch or both deserve that honor. Decide who should be considered the father of microbio and justify why {Ans: Leeuwenkoek's major contribution is the microscope and careful observations of microorganisms and cellular structures Pasteur has many contributions related to vaccines, development of germ theory, disproval of spontaneous generation, development of sterilization procedures and understanding fermentation Koch contributions related to experimental demonstrations of germ theory,