Question

+ Mock Practical 1-1. Read-Only Drew Design Transitions Animations Slide Show ANA des Section BTYS - A L -A- View Rev E Help . Tutenda Dube TD ser x - comments File Shape Arrange Our Shape Outline - - s pect Paragno Sale Q: 3-5 3&4 What type of microorganism is the one under the microscope How can you tell A Note ofte og 105 AM mere to search 2A

Answer 1

Answer 3 & 4: The microscope is showing gram-negative microorganism. As the microorganism has a pink stain, it can be said that they are gram-negative. The gram-negative bacteria have a thin peptidoglycan layer it causes the crystal violet stain to wash out and that the bacteria is stained red or pink due to safranin. Therefore, the microorganism under the microscope is a gram-negative bacteria.

Answer 5 & 6: The microscope is showing gram-positive microorganism. Gram positive microbes have a thick peptidoglycan layer and that does not allow the removal of the crystal violet stain. It helps in retaining the color and thus, the microorganism is stained purple. Therefore, the microorganism under the microscope is a gram-positive bacteria.

Answer 7: The gram reaction that is shown by the pure culture is gram-positive. The bacteria have a rod-shape.

Answer 8: The spore stain of the endospore shows that the bacteria is a non- endospore forming bacteria.

Answer 9: As the bacteria has taken up the safranin stain thus, it is a gram-negative bacteria. The primary stain that is used for endospore staing is green and tus, if gram staing is used then the spore forming bacteria would appear as empty holes under the microscope. However, this is not the case here, as the bacteria has taken by the gram stain and appear pink under the microscope it can be said that it is a non-endospore forming gram-negative bacteria.

Answer 10: Heat is used at the time of endospore staining because the hard coats of protein are made from keratin, and the spores are resistant to the normal process of staining. Thus, in order to drive the primary stain of emdospore staining that is malachite green, the cells are heat fixed.