Which of the following is an integrative system?

Options

A. Excretory system
B. Nervous system
C. Respiratory system
D. Digestive system

Answer

To determine which of the following is an integrative system, let's analyze the options provided: excretory system, nervous system, respiratory system, and digestive system.

### Step-by-Step Solution:

1. **Understanding Integrative Systems**:
- An integrative system is one where various components work together to function as a single unit. These systems are characterized by their ability to process information and coordinate responses.

2. **Analyzing Each Option**:
- **Excretory System**: This system is primarily responsible for the removal of waste products from the body. It performs a specific function but does not integrate multiple functions.
- **Nervous System**: This system is responsible for processing sensory information, integrating that information, and generating appropriate responses (motor output). It involves complex interactions between various components, making it an integrative system.
- **Respiratory System**: This system is focused on the exchange of gases (oxygen and carbon dioxide) and does not integrate multiple functions beyond respiration.
- **Digestive System**: This system is responsible for the breakdown and absorption of nutrients. Like the respiratory system, it performs a specific function without the integration of multiple processes.

3. **Conclusion**:
- Among the given options, the nervous system stands out as the integrative system due to its overlapping functions of sensory input, integration, and motor output. It acts as a control center (the brain) coordinating various activities in the body.

### Final Answer:
The integrative system among the options provided is the **nervous system**.

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