Disease causing agents are known as :-

Answer

**Step-by-Step Solution:**

1. **Understanding Disease**: Begin by defining what a disease is. A disease is a state where the body is adversely affected, which can involve specific organs or the entire system. Diseases manifest through signs and symptoms.

2. **Identifying Disease-Causing Agents**: Recognize that agents that cause diseases are known as disease-causing agents. These agents can lead to various health issues in individuals.

3. **Defining Pathogens**: The term used for these disease-causing agents is "pathogens." Pathogens are organisms or entities that can cause disease in a host.

4. **Types of Pathogens**: Understand that pathogens can be of various types, including:
- **Viruses**: Tiny infectious agents that replicate only inside the living cells of an organism.
- **Bacteria**: Single-celled microorganisms that can be beneficial or harmful.
- **Protozoans**: Single-celled organisms that can cause diseases in humans.
- **Parasites**: Organisms that live on or in a host and derive nutrients at the host's expense.

5. **Conclusion**: Conclude that all these agents, including parasites, are classified under the term "pathogens" because they adversely affect the health of the host.

**Final Answer**: Disease-causing agents are known as **pathogens**.

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