Question

The primitive prokaryotes responsible for the production of biogas from the dung of ruminant animals, include the
A. Halophiles
B. Thermoacidophiles
C. Methanogens
D. Eubacteria

Answer 1

Hint: Some organisms typically found in the oxygen-depleted environments of soils, sediments, and the intestinal tract of humans and animals, which produce methane gas as a metabolic by-product. They also belong exclusively to the archaeal domain of life.

Complete Answer:
To answer this question, first, we need to know about the primitive prokaryotes. The cellular organization of prokaryotic cells is the first cell as they do not consist of a membrane enclosed nucleus and other membrane enclosed cell organelles. Prokaryotes are recognized to be the primitive living organisms of the earth as they are the simplest structure of life. The shape of a prokaryotic cell is not as complicated as eukaryotic cells as they have first cell organelles. The genetic material of prokaryotic cells in a single chromosome is made up of a single strand of DNA.

Now, let us find the solution from the option.
- The halophiles are extremophiles that thrive in high salt concentrations.
- A thermoacidophile belongs to the extremophilic microorganism which includes both thermophilic and acidophilic. It can develop in an environment of maximum temperature and minimum pH.
- Methanogens are found in the abdomen of many ruminant animals like buffaloes and cows, they are the reason for the formation of methane from the waste of these animals.
- Eubacteria are prokaryotic organisms, as characterized by the lack of a membrane-enclosed nucleus, predominantly unicellular, with DNA in a single circular chromosome, and have peptidoglycan in the cell wall when present.

Thus, the correct option is C i.e. Methanogens.

Note: Prokaryotic cells contain no ‘well defined nucleus’ or membrane bound nucleus. Prokaryotes are simple and oldest kinds of cells as prokaryotic cells consist of no ‘well defined nucleuses and the genetic material are found scattered within the cytoplasm of the cell, called nucleoid. These cells do not have membrane bound cell organelles such as mitochondria, Golgi bodies, lysosomes, peroxisomes, ER, etc. All bacteria are prokaryotes, Escherichia coli is the best known prokaryote.