Methanogens do not produce:
a. oxygen
b. methane
c. hydrogen sulfide
d. carbon dioxide
The answer is option (a) oxygen.
Methanogens produce methane, carbon dioxide, and hydrogen sulfide. Methanogens are anaerobic bacteria, meaning they thrive in environments without oxygen. Their primary role is to produce methane gas. Their main byproducts are methane, carbon dioxide, and occasionally small amounts of hydrogen sulfide. They also decompose organic matter, such as cellulose, to generate methane. Therefore, they don't produce oxygen.