Question

A spinal nerve takes nerve signals a. to the CNS. b. away from the CNS. c. both to and away from the CNS. d. from the CNS to the spinal cord.

Short answer

The correct answer is (c) both to and away from the CNS, since spinal nerves transmit sensory information to the CNS and motor information away from the CNS.

Step-by-step solution

Understand the function of spinal nerves and the CNS

Spinal nerves are part of the peripheral nervous system (PNS) and connect the central nervous system (CNS), which includes the brain and spinal cord, to muscles, skin, and internal organs. Spinal nerves transmit sensory information from the body to the CNS and motor information from the CNS to muscles and organs.

Eliminate incorrect options based on spinal nerve function

Now that we know the function of spinal nerves, we can eliminate options that do not align with their purpose: a. If spinal nerves were only taking nerve signals to the CNS, they would only be performing sensory functions and not motor functions. This is not accurate, so option (a) is eliminated. d. Option (d) is also incorrect because it states that spinal nerves transport nerve signals from the CNS to the spinal cord. However, the spinal cord is part of the CNS.

Choose correct option aligned with spinal nerve function

Having eliminated options (a) and (d), our choice is now between options (b) and (c). Option (b) states that spinal nerves take nerve signals away from the CNS, while option (c) states that spinal nerves take nerve signals both to and away from the CNS. As spinal nerves function in transmitting both sensory information to the CNS and motor information away from the CNS, option (c) both to and away from the CNS is the correct answer.

Key concepts

Peripheral Nervous System

The peripheral nervous system (PNS) is like the body's vast communication network, connecting all parts of the body to the central hub, the central nervous system (CNS). While the CNS includes the brain and spinal cord, the PNS extends its reach through spinal and cranial nerves, linking limbs and organs back to the CNS.

There are two main roles of the PNS:

• Sensory Role: It gathers information from the body's environment and sends it to the CNS. This includes all the sensations you feel, like touch, pain, temperature, and more.
• Motor Role: It sends commands from the CNS out to the muscles and glands to produce actions, like moving an arm or adjusting digestion.

The spinal nerves are crucial components of the PNS, acting as highways for sensory and motor signals, ensuring seamless interactions between the body's environment and the brain.

Central Nervous System

The central nervous system (CNS) serves as the control center for the body. It consists exclusively of the brain and spinal cord. Everything the body does, from breathing to speech, is orchestrated by the CNS.

Within the CNS:

• Brain: This is where the processing of sensory information occurs, decisions are made, and instructions are sent out for bodily functions.
• Spinal Cord: Acting as a pathway, it transmits signals between the brain and the rest of the body via spinal nerves.

The CNS receives all the sensory information delivered by the PNS and decides how the body should respond. Then, through motor pathways in the PNS, it sends out commands for appropriate actions, ensuring your body functions smoothly and reacts to its environment.

Sensory and Motor Information

Sensory and motor information form the bedrock of how the nervous system interacts with its environment, creating a dynamic dialogue between perception and action.

Sensory Information: This is how we perceive the world around us. Sensory fibers in the PNS collect data from senses like touch, temperature, and pain and send this information to the CNS. The brain analyzes this data to form a coherent picture of the external environment, enabling us to react appropriately.

Motor Information: Once the CNS has processed sensory information, it issues commands. Motor fibers carry these instructions back through the PNS to effectors, such as muscles and glands. It's through these responses that we perform actions like walking, talking, or even simply blinking.

Together, sensory and motor information enable the body to perform coordinated activities, ensuring our survival and adaptation in a constantly changing world.