Olympiad Test: Microorganisms Friend & Foe - UPSC MCQ

The scientist who study microorganisms are called microbiologists. Microbes are studied by culturing into suitable medium and making their slide.

Microorganisms are found everywhere on earth. They live solitary or in colonies. Most of microbes are either pathogenic or beneficial to human beings.

Microorganisms are either autotrophs that prepare their own food or heterotrophs that obtain their food from other organism. Autotrophic microbes includes unicellular algae, while most of bacteria and virus are heterotrophic.

Cyst is the protective covering that encloses microorganisms during unfavourable conditions. Microbes survive under this cyst to continue perpetuation.

Ethanol fermentation, also called alcoholicfermentation, is a biological process which convertssugars such as glucose, fructose, and sucrose intocellular energy, producing ethanol and carbon dioxide as by-products.

Microbes are present everywhere. They are present in air, water, soil, inside the body of living organisms or parasite including thermal vent and polar ice caps.

Microorganisms live either solitary or in groups. Amoeba is a protozoon that lives solitary or alone in dirty water having irregular shaped body.

On the basis of body shape, bacteria having rod shaped body are called as Bacillus. They may possess cilia or flagella for locomotion.

Microorganisms are used in the production of antibiotics.

Microorganisms are found in everywhere, including hot water springs, ice cold water and marine water. They survive the unfavourable condition by formation of cyst.

Fungi are plant like organisms because the cell of fungi contains cell wall. Chlorophyll is absent in the cell of fungi, hence they are heterotrophic organism.

Pond scums are floating filamentous algae present in stagnant water bodies. Pond scum grows more if organic nutrients are present more in ponds.

 A bacteriophage is a type of virus that infects bacteria. In fact, the word "bacteriophage" literally means "bacteria eater," because bacteriophages destroy their host cells. All bacteriophages are composed of a nucleic acid molecule that is surrounded by a protein structure.

Curd formation from milk requires lactic acid bacteria called Lactobacillus. These bacteria produce lactic acid bacteria by multiplying in number at appropriate temperature.

The ripening of the cheese involves many biochemical changes and this study provides new information on peptides  produced during ripening. Penicillium camemberti is an important mold used in the production of this type of cheese.

The most common yeast associated with winemaking is Saccharomyces cerevisiae which has been favored due to its predictable and vigorous fermentation capabilities, tolerance of relatively high levels of alcohol and sulfur dioxide as well as its ability to thrive in normal wine pH between 2.8 and 4.

Baker's yeast is the common name for the strains of yeast commonly used in baking bread and bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. Yeast is also used in dhokla.

So, it is not used in antibiotics.

Lactobacilli are the bacteria which are naturally present in the milk that convert the sugar(lactose) into lactic acid through the process of fermentation and that is seen in the form of curd.

Athlete’s foot is a fungal disease in human beings. Anthrax and amoebiasis are bacterial disease while amoebiasis is a protozoal disease.

Tobacco Mosaic Virus (TMV) causes disease in tobacco plant. The symptoms of this disease include yellowing of leaves, curling of leaf.

BCG (Bacille Calmette-Guérin) is a vaccine given to babies to protect them from serious forms of Tuberculosis (TB) such as TB Meningitis (an infection of the brain) and Miliary TB (wide spread infection).