The most abundant prokaryotes helpful to human in making curd from milk and in production of antibiotics are the ones categorized as:

1. Cyanobacteria

2. Archaebacteria

3. Chemosynthetic autotrophs

4. Heterotrophic bacteria

Subtopic:  Kingdom Monera: Bacterial Life Process |
 77%
Level 2: 60%+
AIPMT - 2012
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