Microbes in Human Welfare Test - 8

Facultative parasite depends upon other plants or dead organic matter for food.

Bt-gene occurs in Bacillus thuringiensis, a gram-negative, soil-dwelling bacterium which is commonly caused as a biological pesticide.

Due to fermentation, dough kept overnight in warm weather becomes soft and spongy.

Doubling time of bacteria is 35 minutes. Bacteria is grown for 175 minutes. So total number of times bacteria divides is 175/35 = 5 times. Also, 2⁵ = 32.

It means bacteria divides five times. Now, Since the bacteria follows exponential growth after one division population becomes double ie 2n. after 2nd division it becomes  (2²n). After three divisions it becomes, 2*2*2*n ie (2³n). Following the same pattern, after five divisions it will be (2⁵n). Here n is 10⁵cells. Hence, the cell concentration per ml after 175 minutes will be 32 × 10⁵cells.

In cheese manufacturing, the microorganisms (bacteria and fungi) are used. They impart particular texture, taste and flavor to cheese. They are also used for souring of milk and ripening the cheese.

• Cheese is commercially prepared by microorganisms such as bacteria and Fungi.
• Large holed Swiss cheese is ripened with the help of bacterium called Propionibacterium sharmanii.
• Roquefort cheese is ripened by fungi Penicillium roquefortii.
• Camembert cheese is ripened by Penicillium camembertii.

Lactobacillus plantarum is a widespread member of the genus Lactobacillus, commonly found in many fermented food products as well as anaerobic plant matter. Pickles and sauerkraut share this common inoculum.

Spirulina is a cyanobacterium (blue-green algae) that can be consumed by humans and other animals.