Page 34 - MNUmicrobiology practical 2025

General Microbiology & Immunology (PM 401) second level Semester 4 2024/2025

2. Bacillus (rod)

• Bacillus is singular; bacilli is plural

• A bacillus or rod is a hotdog-shaped bacterium having one of the

following arrangements:

A- Bacillus B- Diplobacilli

• Bacilli are the bacteria which are rod-
• Diplobacilli also exists in pairs.
shaped and are present as single cells.
• After cell division, the two cells do

not divide and grow in an attached

arrangement.

C- Streptobacillus D- Coccobacillus

• Bacteria are arranged in chains.

• As the name suggests, coccobacilli
resemble both cocci as well as bacilli.
E- Palisades

Palisades are the type of bacilli bacteria
that resemble a fence structure

General Microbiology & Immunology (PM 401) Practical note Page 23