Nervous System and Neuron Structures

Nervous System

• The nervous system has two main parts: the peripheral nervous system and the central nervous system
• The peripheral nervous system gathers information about the body's environment
• The central nervous system processes this information, creates a response, and sends it through the peripheral nervous system

Neuron Structures

• Dendrites: Short, branched extensions that receive impulses from other neurons
• Nucleus: Located within the cell body
• Cell body: Contains the nucleus and other cellular components
• Axon: A long, slender extension that transmits impulses away from the cell body
• Myelin sheath: An insulating membrane around some axons
• Axon terminal: The end of the axon

Neuron Functions

• Sensory neurons: Carry impulses from the eyes to the spinal cord and brain
• Motor neurons: Carry impulses from the brain and spinal cord to muscles and glands
• Cell body: Has short, branched extensions called dendrites that receive impulses from other neurons.
• Axons and dendrites are often clustered in bundles called nerves

Nervous System Functions

• Collects information about the body's internal and external environment
• Processes this information
• Responds to this information

Nerve Impulse Propagation

• Sodium ions flow into the cell, temporarily making the inside of the cell membrane more positive than the outside
• This reversal of charges causes an action potential

Threshold of a Neuron

• The minimum level of stimulus needed to trigger an impulse in a neuron

Brain and Spinal Cord

• Spinal cord: Main link between the brain and the rest of the body
• Brain stem: Controls vital functions like blood pressure, heart rate, breathing, and swallowing
• Cerebrum: Controls intelligence, learning, and judgment
• Cerebellum: Coordinates muscle actions
• Thalamus: Receives and relays messages from the sense organs
• Hypothalamus: Controls hunger, thirst, fatigue, anger, and body temperature

Peripheral Nervous System

• The sensory division transmits impulses from sense organs to the central nervous system
• The autonomic nervous system controls involuntary activities
• The sympathetic nervous system prepares the body for activity
• The parasympathetic nervous system prepares the body for relaxation

Explore the fascinating components and functions of the nervous system through this informative quiz. Learn about the distinction between the peripheral and central nervous systems and the roles of various neuron structures and types. Perfect for students studying biology or neuroscience.