Question

Complete each of the followinf statements about the importance of chemolithotrophic processes.

Chemolithotrophs have significant ecological impact, making important contributions to several cycles, including the nitrogen, sulfur, and iron cycles. nitrification tin Of great ecological significance are the soil and aquatic bacteria that can carry out , the oxidation of ammonia to nitrate. acidic thiosulfate -oxidizing microbes are the third major group of chemolithotrophs. Sulfur basic The metabolism of and Acidithiobacillus spp. has been best studied. coal These bacteria oxidize sulfur, hydrogen sulfide, -, and other reduced sulfur compounds to sulfuric acid; therefore they have a significant ecological impact. denitrification Thiobacillus Each year millions of tons of sulfuric acid flow to the Ohio River from mines of the Appalachian Mountains. the biogeochemical tricarboxylic acid This sulfuric acid is of microbial origin and leaches enough metals from the mines to make the river reddish and

Answer 1

Chemolithotrophs have significant ecological impact, making important contribution to several biogeochemical cycles, including the nitrogen, sulfur and iron cycles.

Of great ecological significance are the soil and aquatic bacteria that can carry out nitrification, the oxidation of ammonia to nitrate.

Sulfur-oxidizing microbes are the third major group of chemolithotrophs.

The metabolism of Thiobacillus and Acidithiobacillus spp. has been studied.

These bacteria oxidize sulfur, hydrogen sulfide, thiosulfate, and other reduced sulfate compound to sulfuric acid; therefore they have a significant ecological impact.

Each year millions of tons of sulfuric acid flow to the Ohio river from the Coal mines to Appalachian mountains.

This sulfuric acid is of microbial origin and leeches enough metals from the mines to make the river reddish and acidic.

Note: Chemolithotrophs are those organism which obtained energy by oxidizing inorganic compounds such as hydrogen (H2), hydrogen sulfide (H2S), and reduced metals .

Biogeochemical cycle is the movement of essential nutrients such as carbon, hydrogen, nitrogen between different component of ecosystem.

Nitrification is the process of enzymatic oxidation of ammonia to nitrite followed by the oxidation of the nitrite to nitrate by specific nitrifying microorganism. This process is carried out by two types of bacteria.

1: Nitrosomonas carry out the first step of the process, producing nitrite

2: The resulting nitrite is then converted to nitrate by Nitrobacters

Thiobacillus are gram negative, sulfur oxidizing bacteria which is found in both soil and water habitats They produce sulfates which is useful for plants.