Write the characteristic features of the microorganisms which help in the production of biogas in a biogas plant.

(N/A) The microorganisms involved in biogas production are known as methanogens or anaerobic bacteria.
$1$. These microorganisms function in the absence of oxygen,a process known as anaerobic respiration.
$2$. They decompose complex organic matter,such as animal dung and agricultural waste,into simpler substances.
$3$. During this decomposition process,they release a mixture of gases,primarily methane $(CH_4)$,carbon dioxide $(CO_2)$,hydrogen $(H_2)$,and hydrogen sulfide $(H_2S)$,which is collectively known as biogas.