Antibiotics are mostly obtained from

Options

A. fungi
B. actinomycetes
C. cyanobacteria
D. (1) and (2)

Answer

**Step-by-Step Solution:**

1. **Understanding Antibiotics:**
- Antibiotics are substances that inhibit the growth of or kill bacteria. They are primarily used to treat bacterial infections.

2. **Historical Context:**
- The first antibiotic discovered was penicillin, which was derived from a fungus known as *Penicillium notatum*. This discovery was made by Alexander Fleming.

3. **Sources of Antibiotics:**
- **Fungi:** Many antibiotics are produced by fungi. For example, penicillin is produced by the *Penicillium* species.
- **Actinomycetes:** Another significant source of antibiotics is a group of bacteria known as actinomycetes, particularly the genus *Streptomyces*. These bacteria produce several well-known antibiotics, including tetracycline, streptomycin, and erythromycin.

4. **Other Microorganisms:**
- Cyanobacteria, which are a type of bacteria, primarily engage in photosynthesis and nitrogen fixation but are not known for producing antibiotics.

5. **Conclusion:**
- Based on the information, antibiotics are mostly obtained from fungi and actinomycetes. Therefore, the correct answer to the question is that antibiotics are mostly obtained from both fungi and actinomycetes.

**Final Answer:**
Antibiotics are mostly obtained from fungi and actinomycetes.

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