Biology M.C.Q (1 Marks)

c.Souring and ripening.

Nostoc and legumes help in increasing soil fertility by nitrogen fixation in the soil.

Methanogens produce methane, carbon dioxide and hydrogen sulphide.

Methanogenesis is the last step of biogas formation. Methanogenesis or biomethanation is the formation of methane by microbes known as methanogens. In most environments, it is the final step in the decomposition of biomass.

Carbon dioxide creates bubbles in the dough and it leads to rising of dough.

Anthrax disease is caused by Bacillus anthracis. It causes cutaneous infection. This disease is common in dock workers who carry loads. The Rhizobium is fungi and the Clostridium coliform are bacteria related.

Mycorrhiza help the host plant in enhancing its phosphorus uptake capacity, increasing its tolerance to drought and enhancing its resistance to root pathogens.

The nutritive medium for growing bacteria and many fungi in laboratory is called Culture media.
Example, Skoog's medium

Coralloid root of Cycas plant possess cyanobacteria.

Dissolved impurities, toxic substances and harmful bacteria are removal during later processes.

Clostridium acetobutylicum is a commercially valuable bacterium. It produces acetone, ethanol, and butanol from starch at the same time.

Aspergillus is a genus of fungi. The largest application of Aspergillus niger is as the major source of citric acid. The bacteria is useful for the commercial production of citric acid.

Biofertilisers are living micro organisms which bring about soil nutrient enrichment, maximise the ecological benefits, minimise the environmental hazards.

Wine and beer are produced, without distillation. Whisky, brandy and rum are produced by distillation.

Most of the species of Pseudomonas are pathogens; causing diseases in plants and animals.

The aim of the confusion technique is to lay artificial pheromone trails or even to saturate the crop environment with the odour of synthetic pheromone, in order to confuse the males and prevent them from locating females. It is expensive and therefore not usually practical.

Conversion of milk to curd is the right treatment that plays an important role in the micro organism for the well being of humans. Milk will be converted into curd or yogurt based on process of fermentation. Normally, Milk consists of the globular proteins known as casein. Lactic acid bacteria and casein forms a chemical reaction forming curd.

Filaments of Anabaena are found living within ovoid cavities inside the leaves of the Azolla plant. Anabaena azollae maintains a mutually beneficial symbiotic relationship with the water fern Azolla and atmospheric nitrogen with the help of the enzyme nitrogenase present in the heterocysts of the Anabaena. Whereas in return water fern leaves provide shelter to the Anabaena.

Bacillus thuringienesis is a potent agent that can function as a biopesticide.

Antibiotics are chemical substances released by one microorganism either to kill or to pacify other microrganisms, in medicine usually this term is associated with curing of bacterial diseases.

Sludge needs to be subjected to biological treatment which is provided by anaerobic digesters.

An antibiotic is a chemical substance produced by a microorganism that can kill or inhibit the growth of other microorganisms such as bacteria and fungi and thus used to treat bacterial and fungal infections. It kills the bacteria by causing the cell walls to disintegrate.

c.Zymase.

Streptomyces produces clot busters helpful for patients who have undergone myocardial infraction.

A bacterium called Propionibacterium shermanii produces a large amount of carbon dioxide during fermentation. This is the reason of big holes in Swiss cheese.

a.Bacteria.

Butyric acid is a fatty acid found in animal fats and milk such as that of goat, sheep, buffalo etc. It is used to produce butter. When butter goes rancid, butyric acid is liberated from the glyceride by hydrolysis, leading to the unpleasant odour due to anaerobic fermentation.

Cow dung is available in plenty in India. It is used as manure or pattings for fuel. The cow dung solution has antifungal and insecticide properties. The application of cow dung also improves soil salinity and alkalinity. The presence of this manure helps in better nitrogen fixation through rhizobia.

Milk is converted into curd by the action of the bacteria Lactobacillus.
It multiplies and promotes the formation of curd in milk by converting milk protein casein into lactic acid.

Biological control is a component of an integrated pest management strategy. Biological control is keeping the population of organisms or harmful pests and weeds under check by means of natural predators and parasites.

a bacterium producing a large amount of carbon dioxide