Nervous System Flashcards
What is the Nervous System?
A sophisticated communication system that sends and receives electrical impulses throughout the body.
It serves as the control center for bodily functions.
What are the two main portions of the Nervous System?
- Central Nervous System
- Peripheral Nervous System
What makes up the Central Nervous System?
- Brain
- Spinal Cord
What is the role of the Central Nervous System?
Directs the activity of the entire nervous system.
What does the Peripheral Nervous System consist of?
- Cranial Nerves
- Spinal Nerves
- Sensory Receptors
What is the function of Afferent Nerves?
Sends information from Peripheral Nervous System to Central Nervous System.
What is the function of Efferent Nerves?
Sends information from Central Nervous System to Peripheral Nervous System.
What does the acronym SAME stand for?
Sensory, Afferent, Motor, Efferent.
What are the two divisions of the efferent (motor) nerves?
- Somatic Nervous System
- Autonomic Nervous System
What does the Somatic Nervous System control?
Voluntary impulses that stimulate movement.
What does the Autonomic Nervous System control?
Involuntary impulses that regulate functions like heartbeat and digestion.
What is the function of the Parasympathetic Nervous System?
Controls daily functions in a ‘resting and digesting’ state.
What is the function of the Sympathetic Nervous System?
Triggers the ‘fight or flight’ response.
What are the two types of cells in the Nervous System?
- Neurons
- Neuroglia (glial cells)
What are the three parts of a neuron?
- Cell body
- Dendrites
- Axon
What is the role of Neuroglia (glial cells)?
Provide support and protection for the nervous system.
What is the function of Astrocytes?
Connect neurons to capillaries to provide nutrients.
What is the role of Oligodendrocytes?
Wrap around nerve fibers and produce myelin in the CNS.
What is the purpose of the myelin sheath?
Insulates axon fibers and increases the rate of nerve transmission.
What are the gaps in the myelin sheath called?
Nodes of Ranvier.
What is the synaptic cleft?
The gap between the axon terminal and the next neuron or muscle cell.
What are neurotransmitters?
Chemical messengers released from axon terminals.
What is a nerve impulse also known as?
Action potential.
What initiates a nerve impulse?
A stimulus, such as a bright light or a bitter taste.
What is Saltatory Conduction?
The jumping of action potentials from one Node of Ranvier to another.
How does temperature affect nerve impulse conduction?
Warmer body temperatures increase conduction speed.
What are reflexes?
Simple, rapid involuntary responses to stimuli.
Where do reflexes typically go?
From the neuron to the spinal cord and back via interneurons.
