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 & explanation
Answer: (c) 1 and 3
Statements 1 and 3 are correct. Probiotics are live microbes, mostly bacteria but also some yeasts, and certain probiotic bacteria help digest lactose, the sugar in milk. Statement 2 is wrong because many probiotic organisms are the same as or similar to microbes that already live naturally in our body.
- ✓ 1. Most probiotics are bacteria (Lactobacillus and Bifidobacterium are the commonest), but some are yeasts such as Saccharomyces boulardii.
- ✗ 2. Many probiotic microbes are the same as or similar to those that naturally live in our bodies. NCERT too notes that lactic acid bacteria in our stomach help check disease-causing microbes.
- ✓ 3. Probiotic bacteria that carry the enzyme beta-galactosidase help break down lactose. Yogurt cultures such as L. bulgaricus and S. thermophilus give a similar benefit to people who cannot digest milk sugar well.
Remember · Probiotics: live microbes, mostly bacteria (Lactobacillus, Bifidobacterium) plus some yeasts; they resemble our natural gut flora and can ease lactose digestion.
📘 Read it in NCERT: Class 12 Biology, Ch 8 (practise this chapter)
Sources
- NIH National Center for Complementary and Integrative Health, Probiotics: Usefulness and Safety (Internet Archive copy) ↗ “The most common are bacteria that belong to groups called Lactobacillus and Bifidobacterium . Other bacteria may also be used as probiotics, and so may yeasts such as Saccharomyces boulardii . … Many of the microorganisms in probiotic products are the same as or similar to microorganisms that naturally live in our bodies.”
- FAO/WHO, Probiotics in food: health and nutritional properties and guidelines for evaluation ↗ “Probiotic bacteria containing β-galactosidase can be added to food to improve lactose maldigestion”
- NCERT Class 12 · Biology, Chapter 8 “In our stomach too, the LAB play very beneficial role in checking disease- causing microbes.”
Question and answer: UPSC's official GS Paper I (2022, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·