Question map
Consider the following : 1. Bacteria 2. Fungi 3. Virus Which of the above can be cultured in artificial/synthetic medium?
Explanation
The correct answer is Option 1 (1 and 2 only). This distinction is based on the fundamental biological nature of the organisms involved.
- Bacteria and Fungi: These are independent living organisms. They possess the necessary cellular machinery for metabolism and reproduction. They can be grown in laboratories using artificial or synthetic media (such as agar or nutrient broth) that provide essential nutrients like carbon, nitrogen, and vitamins.
- Viruses: Unlike bacteria and fungi, viruses are obligate intracellular parasites. They lack their own metabolic machinery and cannot replicate outside a living host cell. Therefore, they cannot be cultured in synthetic, non-living media. They require living systems, such as cell cultures, embryonated eggs, or whole organisms, for cultivation.
Since bacteria and fungi can thrive on artificial nutrients while viruses cannot, only statements 1 and 2 are correct.
PROVENANCE & STUDY PATTERN
Full viewThis is a fundamental 'Definition of Life' question disguised as a technology question. It relies entirely on the Class VIII/XI NCERT definition of a Virus as an 'obligate parasite' that lacks its own metabolic machinery. If it can't metabolize, it can't 'eat' synthetic nutrients; it needs a living host to hijack.
This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.
- Explicitly states microorganisms obtain required nutrients from media used in microbiology.
- Says culture media include natural and synthetic culture medium and that culturing is an established discipline.
- States that culture medium provides essential environmental requirements for cell proliferation.
- Describes that the type of medium affects productivity and many substances are added to media to support growth.
Describes cells placed in an artificial medium where they divide and form callus — establishes that living cells can be grown outside the organism in a man-made nutrient medium.
A student could generalize that if plant cells grow in artificial media, microorganisms (which are simpler/smaller) might also be grown in appropriately formulated artificial media under controlled conditions.
States that bacteria grow and act under optimal temperature and moisture and decompose wastes — highlights that microbes have specific physical and chemical requirements for growth.
A student could infer that supplying those optimal conditions (temperature, moisture, nutrients) in an artificial medium could support bacterial growth in the lab.
Explains that Lactobacillus causes curd formation in milk — an example of bacteria proliferating in a nutrient-containing medium (milk) supplied by humans.
A student could analogize that milk is a natural culture medium and reason that synthetic media could be formulated with similar nutrients to culture bacteria artificially.
Notes that yeasts and Lactobacillus are used in food processes and industry — implying humans manage and harness microbial growth for specific outcomes.
A student might extend this to the idea that industries cultivate microbes under controlled conditions using prepared media, suggesting artificial media can support microbial growth.
- Describes placing removed cells in an artificial medium where they divide and form callus.
- Demonstrates that living cells can be grown and induced to differentiate in vitro using synthetic media.
- Provides the laboratory principle of culturing cells outside the organism which is applicable to other microbes.
- Identifies yeast as a fungus (unicellular), establishing a fungal example amenable to controlled growth.
- Makes yeast a clear candidate organism for laboratory or industrial propagation.
- States yeasts are used in bread and fermentation processes, implying propagation under human-controlled conditions.
- Provides a practical example of fungi being grown/used outside their natural substrate.
- Directly states that viruses multiply when they enter a living cell.
- Implies viral replication depends on living host cellular machinery, not on acellular media.
- Explicitly notes viruses reproduce only inside the host organism.
- Contrasts viruses with other microorganisms that can reproduce independently, supporting the need for hosts.
- Notes viruses show no molecular activity until they infect a cell, implying inactivity outside host cells.
- Supports the view that viral life processes (and thus replication) require a host cell environment.
- [THE VERDICT]: Sitter. Directly solvable from NCERT Class VIII (Ch 2: Microorganisms) and Class XI (Biological Classification).
- [THE CONCEPTUAL TRIGGER]: The distinction between 'Cellular' life (Bacteria, Fungi, Protists) and 'Acellular' agents (Viruses, Viroids, Prions).
- [THE HORIZONTAL EXPANSION]: 1. Bacteria: Prokaryotic, grow on Nutrient Agar. 2. Fungi: Eukaryotic, grow on Sabouraud Dextrose Agar. 3. Virus: Acellular, requires living cells (Chick embryo, Vero cell lines). 4. Mycoplasma: The smallest bacteria, *can* grow on cell-free media (exception to size rule). 5. Rickettsia/Chlamydia: Bacteria that are obligate intracellular parasites (cannot grow on artificial media) – the tricky exception.
- [THE STRATEGIC METACOGNITION]: Apply the 'Machinery Test'. Does the organism have ribosomes and enzymes to process food? If Yes (Bacteria/Fungi) -> Artificial Media works. If No (Virus) -> Needs a host. Don't memorize lists; memorize metabolic capabilities.
Plant cells can be placed in an artificial medium to grow and differentiate, demonstrating the principle of supplying nutrients and conditions ex vivo.
High-yield for questions on biotechnology and laboratory methods: explains the basic idea of growing organisms outside their natural environment and links to sterilization, nutrient formulation, and tissue/cell culture techniques. Useful across biology, agriculture, and applied microbiology questions.
- Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > Tissue culture > p. 118
Microorganisms occur widely in soil, water, air and on food, showing accessible sources and diverse growth conditions for microbes.
Important for ecology and microbiology sections: helps explain sampling, isolation of microbes, and environmental influences on microbial growth; connects to biodegradation, nitrogen fixation, and public health topics.
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > 2.4 How Are We Connected to Microbes? > p. 18
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Our scientific heritage > p. 19
Yeasts and Lactobacillus are deliberately used to grow and transform food substrates, illustrating practical cultivation of microbes for industry.
Directly relevant to questions on food technology, industrial microbiology and rural economy: shows applied use of microbial growth, scaling of cultures, and links to topics like fermentation, food security and traditional industries.
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Snapshots > p. 25
Tissue culture explains growth of cells in an artificial medium where cells divide and differentiate, forming the basis of in vitro cultivation.
High-yield for UPSC biology and biotechnology topics because it underpins laboratory cultivation methods used in research, agriculture and industry. Connects to microbiology (culture techniques), plant propagation, and applied biotech questions about growing organisms outside their natural environment.
- Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > Tissue culture > p. 118
Yeast is a unicellular fungus commonly used in bread and fermentation, showing fungi can be propagated under controlled conditions.
Important for answering questions on microbes in food technology, industrial microbiology and life processes. Mastering yeast as an example helps bridge fungal biology, fermentation industries, and practical culturing concepts in exam questions.
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > 2.5 Why Is Cell Considered to Be a Basic Unit of Life? > p. 23
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Snapshots > p. 25
Viruses are acellular and replicate only inside living host cells, which determines that they cannot be grown in purely cell‑free media.
High-yield for biology and public health: explains viral life cycle, diagnostic propagation methods, and why viral cultivation differs from bacterial culture; links to virology, immunology, and vaccine production questions. Mastering this helps answer questions on culturing requirements and treatment strategies.
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Ever heard of ... > p. 17
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Snapshots > p. 24
Living organisms are made of cells and can be grown or maintained using cell‑based culture techniques, unlike acellular agents such as viruses.
Fundamental across biology topics: underpins tissue culture, microbial growth methods, and biotechnology; helps distinguish methods applicable to bacteria/fungi versus viruses, useful in questions on laboratory techniques and biomanufacturing.
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > 2.1 What Is a Cell? > p. 10
- Science , class X (NCERT 2025 ed.) > Chapter 7: How do Organisms Reproduce? > Tissue culture > p. 118
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 2: The Invisible Living World: Beyond Our Naked Eye > Snapshots > p. 24
Rickettsia and Chlamydia. These are technically bacteria (have cells/DNA/RNA) but behave like viruses (obligate intracellular parasites) and generally cannot be cultured on simple synthetic media. They are the likely 'trap' for a future question on microbial exceptions.
The 'Zombie Logic': A virus is effectively 'dead' (crystallizable) outside a host. Dead things cannot eat or grow on a plate of food (synthetic medium). Therefore, Statement 3 is impossible. Eliminate options containing 3 ([B], [C], [D]). Answer is [A].
Mains GS-3 (Science & Tech - Vaccines): This concept dictates vaccine manufacturing. 'Inactivated vaccines' (Covaxin) require growing viruses in living cells (Vero cells), making production slower/harder. 'mRNA vaccines' (Pfizer/Moderna) skip the culture step entirely by synthesizing the code chemically. This explains why mRNA production is faster.