Are the bacteria living in a cows stomach to digest cellulose Autotrophes?

Cellulose-digesting bacteria are heterotrophic ones because they use organic carbon compounds (produced by other living organisms), not CO2, as a source of carbon.





There are some bacteria in rumen which perform a reaction H2 + CO2 to produce methane. This multi-step pathway is mainly a source of energy for the bacterial cells, not a tool to build up new organic cell compounds from CO2 (like photosynthetic organisms like plants do, aided by solar energy).





Autotrophy in methanogenesis can, however, occur if an anabolic ("building") metabolic route, called acetyl-CoA pathway, is connected in methanogenesis. In these cases synthesis of new organic material from CO2 (= autotrophy) really occurs.





The diversity of rumen's bacterial population is huge and several methanogenic species also live in rumen. If there are species which use CO2 and H2 not only for the production of energy but also for anabolic purposes, they can be called autotrophes.





But - back to your original question - cellulose-digesting bacteria do not belong to autotrophes - they are heterotrophes, depending on the organic compounds produced by other organisms.

Are the bacteria living in a cows stomach to digest cellulose Autotrophes?
Microbes in the reticulorumen include bacteria, protozoa, fungi, archea, and viruses. Bacteria, along with protozoa, are the predominant microbes and by mass account for 40-60% of total microbial matter in the rumen. They are categorized into several functional groups, such as fibrolytic, amolytic, and proteolytic bacteria, which preferentially digest structural carbohydrates, non-structural carbohydrates, and protein, respectively. Protozoa (40-60% of microbial mass) derive most of their nutrients through phagocytosis of other microbes, though they also degrade and digest food carbohydrates, especially structural carbohydrates, and protein. Ruminal fungi make up only 5-10% of microbes. Despite their low numbers, the fungi still occupy an important niche in the rumen because they can solubolize recalcitrant lignin, which makes available nutrients that were previously bound by the lignin. Rumen archea, approximately 3% of total microbes, are autotrophic methanogens and produce methane through anaerobic respiration
Reply:If the organism is metabolizing an organic compound for energy, it is a heterotroph. Cellulose is an organic compound.


If is is using inorganic compounds or elements (like oxidation of iron), it can be an autotroph of the chemoautotroph variety.
Reply:The short answer is, NO. Autotrophs produce their own food. Bacteria recycle other organic substances. Autotrophs come in two types, as far as I know. You have Heliotrophs (Phototrophs) that do photosynthesis and Chemotrophs that depend on inorganic chemicals to produce organic substances.


Heliotroph are usually plants and Chemotrophs live in deep sea vents or near boiling water in mineral springs etc. Chemotrophs were only discovered about 1978. It is the first type live was found that is NOT dependent on the sun.


Bacteria depend on some organic substance to break down. Therefor, they are dependent on other forms of live to provide what they need to survive.


I hope this helps out and gives you a better understanding.