Adaptive/acquried immunity is found in

Options

A. Vertebrates
B. Invertebrates
C. Plants
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Adaptive/Acquired Immunity**:
- Adaptive immunity, also known as acquired immunity, is a specialized immune response that develops over time. It is characterized by the ability to recognize specific pathogens and remember them for future encounters.

2. **Identifying the Organisms with Adaptive Immunity**:
- Adaptive immunity is primarily found in vertebrates, which include animals with a backbone such as mammals, birds, reptiles, amphibians, and fish.

3. **Function of Adaptive Immunity**:
- The adaptive immune system has two main functions:
- Elimination of pathogens (such as bacteria and viruses).
- Prevention of pathogen growth.

4. **Immunological Memory**:
- One of the key features of adaptive immunity is the creation of immunological memory. After the initial exposure to a specific pathogen, the immune system "remembers" it, allowing for a faster and more effective response upon subsequent exposures.

5. **Conclusion**:
- Based on the characteristics and functions of adaptive immunity, it is clear that it is predominantly found in vertebrates. Invertebrates and plants do not possess the same type of adaptive immune response.

6. **Final Answer**:
- Therefore, the correct answer to the question "Adaptive/acquired immunity is found in" is option A: vertebrates.

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