Question

Obligate anaerobes require
a. Oxygen
b. Carbon Dioxide
c. Methane
d. No oxygen

Answer 1

Hint: With the help of anaerobic respiration, obligate anaerobes to metabolize energy. Within aerobic respiration, the pyruvate created from glycolysis is changed to Acetyl-CoA. This is subsequently broken down by means of the TCA cycle and electron transport chain. Anaerobic respiration varies from aerobic respiration in that it utilizes an electron acceptor other than oxygen in the electron transport chain.

Complete answer:
The organisms which respire in the absence of oxygen are Anaerobes. Obligate anaerobes are those microorganisms that are unable to survive in the occurrence of oxygen. They use fermentation to create the energy vital for the metabolic process. Oxygen is injurious to these organisms. The deficiency of the enzymes superoxide dismutase and catalase is responsible for death in the presence of oxygen.

Obligate anaerobes are microorganisms eradicated by normal atmospheric concentrations of oxygen (20.95% O2). Oxygen acceptance varies between species, some proficient in surviving in up to 8% oxygen, others losing viability until the oxygen concentration is less than 0.5%.

Aerobe is an organism that can live and produce in presence of oxygen. Methanogens, which relates to the Euryarchaeota kingdom of Archaea, attain energy for development by reducing carbon dioxide to methane with hydrogen gas or formate as an electron-donating reductant.

Hence, the correct answer is option (D).

Note: Obligate anaerobes do not contain numerous key enzymes required to detoxify oxygen in the cell. Oxygen in the presence of water makes several byproducts counting hydrogen peroxide. Hydrogen peroxide is a feeble acid and influences a number of enzymes within anaerobic cells. In soaring levels of oxygen, the cell turns out to be so acidic that it can no longer be used.