Consider the following statements in respect of probiotics: 1. Probiotics are made of both bacteria and yeast. 2. The organisms in probiotics are found in foods we ingest but they do not naturally occur in our gut. 3. Probiotics help in the digestion of milk sugars. Which of the statements given above is/are correct?

Answer: C. Statements 1 and 3 are correct; Statement 2 is wrong. Probiotics are live microorganisms that, when administered in adequate amounts, confer health benefits on the host. Statement 1 is CORRECT. Probiotics include BOTH BACTERIA (Lactobacillus, Bifidobacterium, Lactococcus, Streptococcus) AND YEAST (Saccharomyces boulardii is the most commonly used probiotic yeast for treating diarrhoea). So probiotics span both bacterial and fungal microorganisms. Statement 2 is WRONG. Probiotic organisms are found in FOODS we ingest (yogurt, kefir, kimchi, sauerkraut) AND they DO naturally occur in the human gut. The human gut microbiome contains trillions of microbes including many probiotic-type genera. Probiotic supplements supplement existing gut populations rather than introduce alien organisms. Statement 3 is CORRECT. Probiotics help digest MILK SUGARS (lactose). Lactobacillus and similar bacteria produce LACTASE enzyme that breaks down lactose into glucose and galactose. This is why probiotic yogurt is often tolerated by lactose-intolerant individuals. Source: NCERT Class 12 Biology Ch 10 / WHO probiotics definitions / FAO joint guidelines.