Name two diseases caused by protozoans. What are their casual organisms?

Explanation

### Step-by-Step Solution:

1. **Identify Two Diseases Caused by Protozoans**:
- The first disease is **Malaria**.
- The second disease is **Kala Azar**.

2. **Identify the Causal Organisms**:
- The causal organism for **Malaria** is **Plasmodium**.
- The causal organism for **Kala Azar** is **Leishmania**.

3. **Summarize the Information**:
- **Malaria**: Caused by **Plasmodium**; transmitted by the female Anopheles mosquito.
- **Kala Azar**: Caused by **Leishmania**; associated with specific symptoms like recurrent fever and swelling of the spleen or liver.

### Final Answer:
- Two diseases caused by protozoans are:
1. **Malaria** (causal organism: **Plasmodium**)
2. **Kala Azar** (causal organism: **Leishmania**)

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