Read the given passage and answer the following question:
Microbes like Saccharomyces cerevisiae are utilised in the commercial production of ethanol. Enzyme production is another application of microbes, with lipases being used in detergent formulations to effectively remove oily stains from laundry. It is common to observe that commercially bottled fruit juices appear clearer compared to homemade ones, as the former undergo clarification processes employing pectinases and proteases. Streptokinase, produced by the bacterium Streptococcus and genetically modified, serves as a "clot buster" in the removal of blood clots from the vessels of individuals who have experienced a heart attack. Cyclosporin A, another bioactive molecule, is derived from the fungus Trichoderma polysporum and is employed as an immunosuppressive agent in organ transplant patients. Statins, on the other hand, are produced by the yeast Monascus purpureus and have been commercialised as agents to lower blood cholesterol levels. They function by competitively inhibiting the enzyme responsible for cholesterol synthesis. Biofertilisers are organisms that enhance the nutrient quality of the soil and can be derived from bacteria, fungi, and cyanobacteria. Rhizobium bacteria form nodules on the roots of leguminous plants and convert atmospheric nitrogen into organic forms, which serve as nutrients for the plants. Additionally, certain free-living bacteria like Azospirillum and Azotobacter can fix atmospheric nitrogen in the soil, thereby enriching its nitrogen content. Fungi also engage in symbiotic associations with plants, known as mycorrhiza. Many members of the Glomus genus form mycorrhiza, wherein the fungal symbiont absorbs phosphorus from the soil and transfers it to the plant. These associations offer various benefits to the plants, including enhanced resistance to root-borne pathogens, increased tolerance to salinity and drought, and an overall improvement in plant growth and development.
The large holes in ‘Swiss cheese’ are due to the production of a large amount of CO2 by:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Propionibacterium sharmanii
Each variety of cheese gets its texture, flavour and taste from the microbes used to make it. In Swiss cheese, the bacterium Propionibacterium sharmanii gives off a large amount of carbon dioxide. The gas is trapped in the cheese and forms the large holes. Another example from the book is Roquefort cheese, which is ripened by growing a specific fungus on it.
NCERT Extract:
Microbes in Household Products – “… Cheese, is one of the oldest food items in which microbes were used. Different varieties of cheese are known by their characteristic texture, flavour and taste, the specificity coming from the microbes used. For example, the large holes in ‘Swiss cheese’ are due to production of a large amount of CO2 by a bacterium named Propionibacterium sharmanii. The ‘Roquefort cheese’ are ripened by growing a specific fungi on them, which gives them a particular flavour.”