An organism reduces survival, growth and reproduction of other organism, reduces its population density and make it physically weak, such organism are called _______.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question describes an organism that negatively impacts the survival, growth, and reproduction of other organisms, reduces their population density, and makes them physically weak.

2. **Identifying the Type of Organism**: The key characteristics mentioned—reducing survival, growth, and reproduction—suggest that the organism in question interacts with others in a way that is detrimental to them.

3. **Defining the Term**: Based on the description, the organism that fits this definition is known as a "predator." Predators are organisms that hunt and kill other organisms (prey) for food.

4. **Examples of Predators**: Common examples of predators include lions, tigers, and snakes. These animals hunt other animals, which leads to a decrease in the population density of their prey.

5. **Conclusion**: Therefore, the organism that reduces the survival, growth, and reproduction of other organisms, and makes them physically weak, is called a **predator**.

**Final Answer**: Predators

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