Question

33. Presence of capsule around the
bacterial cells is generally viewed by​

Answer 1

Answer:

To visualize encapsulated bacteria using a microscope, a sample is treated with a dark stain, such as India ink. The structure of the capsule prevents the stain from penetrating the cell. When viewed, bacterial capsules appear as a bright halo around the cell on a dark background.

Quellung test

Quellung test is a serological test done for the demonstration of capsule wherein the bacteria are probed with specific anticapsular antibodies and are later stained and observed under the microscope. The capsule is seen as an increase in the halo surrounding the bacteria.

Answer 2

Explanation:

The association of virulence and capsule formation is also found in many other species of bacteria. The capsular material surrounding these bacteria (Acinetobacter calcoaceticus) is revealed in a suspension of India ink and viewed through a light microscope (magnified about 2,500×).