Streptococcus thermophilus
Streptococcus penicillium
Penicillium roqueforti
Aspergillus niger
Step 1: Role of microorganisms in yoghurt production.
Yoghurt is produced through the fermentation of milk using specific bacteria. \textit{Streptococcus thermophilus} and \textit{Lactobacillus delbrueckii subsp. bulgaricus} are commonly used starter cultures.
Step 2: Explanation of other microorganisms.
Streptococcus penicillium (Option B):} Incorrect. This is not a known species used in yoghurt production.
Penicillium roqueforti (Option C):} Incorrect. This fungus is used in the production of blue cheese, not yoghurt.
Aspergillus niger (Option D):} Incorrect. This fungus is used for industrial production of citric acid, not yoghurt. \[ \therefore \text{The correct answer is: Streptococcus thermophilus
Answer the following questions:
1. State what do you understand by “MALT”? Where is it located inside our body?
2. Explain cytokine barriers.
3. Name the diagnostic test for AIDS. On what principle does it work?
4. Bone marrow and thymus play an important role in human immune system. Explain how are they able to achieve this.
Name an alcoholic drink which is produced with the help of microbes:
(1) With distillation
(2) Without distillation