The Nervous System and Its Role in Coordinating Physiological Responses

1. The nervous system is a specialised network of cells (neurons) that communicate electrical signals throughout the body.
2. It enables the body to sense and respond to internal and external stimuli, maintaining homeostasis through coordinated regulation of physiological processes.

Basic structure of the nervous system

Key Functions of the Nervous System

1. Sensory Input: Detects changes in the internal and external environments.
2. Integration: Processes and interprets sensory input.
3. Motor Output: Initiates responses to changes, such as muscle contraction or gland secretion.

Main divisions of the nervous system

The nervous system is divided into two main parts:

1. Central Nervous System (CNS)
   1. Components: Brain and spinal cord.
   2. Function: Serves as the control centre of the body, processes information, and sends instructions to the body.
2. Peripheral Nervous System (PNS)
   1. Components: Nerves extending from the spinal cord to the rest of the body (limbs, organs, etc.).
   2. Function: Connects the CNS to the limbs and organs, transmitting sensory information to the CNS and motor commands from the CNS to muscles and glands.

Central Nervous System

The CNS consists of the brain and spinal cord and is responsible for processing information, making decisions, and directing responses.

Brain

1. The brain integrates sensory input and generates responses.
2. It is involved in everything from conscious thought to unconscious functions like breathing.

Major brain areas and their functions

1. Cerebrum: The largest part of the brain, responsible for higher brain functions such as thought, memory, and voluntary movement.
2. Cerebellum: Coordinates voluntary movements and balance.
3. Brainstem: Controls vital functions like heart rate and breathing.

Spinal Cord

1. The spinal cord relays messages between the brain and the rest of the body.