Question

Lactobacillus} that sets milk into curd is categorised as:

• A. Cyanobacteria
• B. Archaebacteria
• C. Chemosynthetic bacteria
• D. Heterotrophic bacteria

Hint:

Bacteria like Lactobacillus} help in fermentation and curd formation by anaerobic breakdown of lactose — a heterotrophic process.

Answer 1

The Correct Option is D

Lactobacillus} is a genus of bacteria that plays a major role in the curdling of milk by converting lactose (milk sugar) into lactic acid.
These bacteria are dependent on external organic substances for nutrition, making them heterotrophic.
Let’s eliminate other options:
- Cyanobacteria are autotrophic and photosynthetic, not involved in curd formation.
- Archaebacteria are ancient extremophiles found in harsh conditions like hot springs, not in curd.
- Chemosynthetic bacteria obtain energy from inorganic chemical reactions, not involved in dairy fermentation.
Hence, Lactobacillus} is correctly classified as heterotrophic bacteria.