Tag: archaebacteria

The archaebacteria are the primitive, single-celled, prokaryotic organisms. These are the ancient and oldest living organisms. These were the first organism which evolved on the Earth. These organisms have evolved to survive in the extreme conditions like the halophiles, thermophiles, acidophiles, methanogens, etc. 

Thermophilic sulphur bacteria are found in hot springs and multiply at temperatutures 100-105$^0$C

The term Obligate anaerobes represent such microorganisms which can survive only in the absence of oxygen, i.e. presence of oxygen in their surrounding environment acts as a poison for them. Methane bacteria also called as methanogens are methane-producing bacteria which are obligate anaerobes as their metabolic processes do not require oxygen. Spirogyra are the green algae which produces oxygen. Pisum Sativum is commonly known as Green pea, which is a vegetable. Onion is also a vegetable.

The correct answer is D. 

Methanogens are responsible for methane gas production in biogas. Methanogen belongs to Archaebacteria class. Archeae are prokaryotic bacteria. They have no cell nucleus. They were initially classified as bacteria and hence called as Archaebacteria. 

• Halophiles are the prokaryotes that can be aerobic or anaerobic. 
• The phototropic anaerobic halophiles can trap solar energy for the synthesis of ATP i.e Adenosine Triphosphate with the help of ATP synthase enzyme. ATP is also known as the energy currency of a cell.
• The correct answer is C.

Methanogens are microorganisms that produce methane in absence of oxygen by the process called as methanogenesis. They belong to the kingdom Monera and the domain archaea. They use inorganic material as the source of energy such as hydrogen sulfide, elemental sulfur, ferrous iron, ammonia. They reduce carbon dioxide to methane and use hydrogen gas as an electron-donating reductant.

Clostridium bacteria is one of the most cause of food poisoning. It is a rod-shaped Gram-positive bacteria. It is a causative agent of botulism disease. It is a gas forming bacteria. It causes causative agent of botulism Gas gangrene by producing gas in tissues in gangrene.

Obligate anaerobes are organisms which grow in absence of oxygen. In presence of oxygen, they cannot survive. The example includes methane producing bacteria or methanogens.  They obtain their energy without consumption of oxygen. Other examples include Clostridium species.

Halophiles are organisms that thrive in high salt concentrations. They are also called as salt-loving microorganisms. Majority of halophiles belongs to Archaebacteria group. They are found in hypersaline environments like in arid, coastal, deep‐sea, underground salt mines. They can comfortably live in evaporation ponds or salt lakes, salt pans and salt marshes.