The most abundant prokaryotes helpful to humans in making curd from milk and in production of antibiotics are the ones categorised as:
Cyanobacteria
Archaebacteria
Chemosynthetic autotrophs
Heterotrophic bacteria
The correct option is Option 4) Heterotrophic bacteria.
The most abundant prokaryotes that are helpful to humans in making curd from milk and in the production of antibiotics are the ones categorized as heterotrophic bacteria. These bacteria play a crucial role in various industrial processes, including the fermentation of milk to produce curd and the production of antibiotics.
In the process of making curd from milk, certain bacteria, such as Lactobacillus and Streptococcus species, are used. These bacteria convert lactose, the primary sugar present in milk, into lactic acid through fermentation. This acidification process leads to the coagulation of milk proteins, resulting in the formation of curd.
Additionally, in the production of antibiotics, many important antibiotics are derived from various species of bacteria. Examples include Penicillin from Penicillium species and Streptomycin from Streptomyces species. These bacteria have the ability to produce bioactive compounds that inhibit the growth of other microorganisms, making them valuable sources of antibiotics.