Question

Mention the role of Methanobacterium in the rumen of cattle.

Answer 1

Hint: Some methanogenic archaea live as symbionts (such as methane bacteria) in the stomach or the first room of the stomach of herbivores (ruminants such as cows and buffaloes). Archaea are beneficial in the fermentation of cellulose in ruminants.

Complete answer:
The stomach of ruminants is known as a compound stomach. It has four well-defined chambers or compartments rumens, reticulum, omasum, and abomasum. The rumen is the first and largest chamber mainly for the storage of food. Digestion of cellulose takes place by fermentation with the help of methanobacterium with the help of Methanobacterium, other symbiotic bacteria, and protozoan.
 Food containing saliva is first directed towards the rumen to break it down into smaller particles, then passed on to the reticulum, where the food is broken down into smaller particles and the indigestible particles are sent back to the rumen to be chewed again and then. Most of the anaerobic microbes that help break down cellulose occupy the scars. They start the fermentation process.
 These animals absorb fatty acids, vitamins, and nutrients during the transition of partially digested feed from worms to omasum, lowering the pH and thereby initiating the release of enzymes for a further breakdown of the feed, wherein the abomasum is then transferred, which absorbs other nutrients before excretion. This process takes about 9-12 hours.

Note:
> Abomasum is the true stomach, which secretes gastric juices.
> Rumen and reticulum harbor large populations of anaerobic cellulosic bacteria like Rumen coccus which secrete the cellulase enzyme for the fermentation of cellulose.
> In camels and deer, omasum is absent and water cells project from the rumen.
> Methanobacterium are strictly anaerobic bacteria. In terms of nutrition, it is an "autotrophic organism" that receives energy and carbon from decomposition products. They are found in swamps and use hydrogen to convert formic acid and carbon dioxide to methane. This function is used commercially for the production of methane and gaseous fuels in gas systems from gases.