OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

Why is the brain and spinal cord considered the central nervous system?

1. They transmit chemical signals throughout the body

2. They perform all executive control functions in the body

3. They integrate information and coordinate responses

4. They are the only parts of the nervous system that are active

The correct answer is: They integrate information and coordinate responses

The brain and spinal cord are considered the central nervous system because they play a crucial role in integrating information and coordinating responses throughout the body. The brain processes sensory information, making sense of the signals received, while the spinal cord acts as a conduit for signals between the brain and the rest of the body. Together, they enable reflex actions and complex responses to stimuli, ensuring that the body can react appropriately to various internal and external changes. This integration of information is essential for many functions, such as voluntary movements, thoughts, emotions, and the regulation of bodily systems. By responding to sensory inputs and coordinating signals to muscles and glands, the central nervous system orchestrates a wide range of physical activities and adaptive responses that facilitate survival and interaction with the environment.