The Nervous System Flashcards
Function of the Central Nervous System
A rapid communication system which acts as the main coordinator of body functions.
- Regulates the internal environment
- Regulates and coordinates all other body systems (including higher functions ie. thinking, reasoning, emotions)
How does the nervous system communicate?
Through the use of electrical and chemical signals carried out by neurons.
Basic structures of the Neuron
- Dendrites
- Cell body
- Axon
- Axon terminals
How is information sent through the Nervous System?
- Information comes in through the sensory receptors (eys, skin, fingers, etc).
- It is transmitted as sensory input to the CNS (brain and spina cord).
- The CNS integrates this information.
- The CNS sends motor output out to the body.
- This output triggers the effector, causing muscles to move according to the signal sent.
Parts of the Central Nervous System
(CNS)
The CNS is made up of the brain and the spinal cord.
Thes organs contain neural tissue, blood vessels and connective tissues.
Parts of the Peripheral Nervous System
PNS is comprised of the cranial and spinal nerves and all nerves outside the CNS.
Function of the CNS
Integrates, processes and coordinates sensory data and motor commands.
Function of the PNS
Sends sensory data from the sense organs to the CNS and motor commands from the CNS to the peripheral tissues and organs.
Two Divisions of the Peripheral Nervous System
- Afferent Division - sensorty data from the sense organz to the CNS
- Efferent Division - Motor commands from the CNS to the effector organs
Two Parts that Make up the Efferent Division of the PNS
- Somatic Nervous System - controls muscle contractions
- Autonomic Nervous System - Controls reflexes, organs and tissues not under voluntary control.
What is the Efferent Division of the Nervous System?
Part of the Peripheral Nervous Sytem.
Controls motor commands from the CNS to the effector organs.
What is the Afferent Division?
Part of the PNS.
Nerves pass sensory information from the sense organs to the CNS.
Somatic Nervous System
Controls skeletal muscle contractions. Conscious ability to move your muscles.
Autonomic Nervous System
Controlled at subconscious level.
This includes reflex actions, all organs and tissues not under voluntary control (including smooth muscle of the walls of airways and blood vessels).
Separated into two systems:
- Sympathetic
- Parasympathetic
Two Parts of the Autonomic Nervous system
- Sympathetic - mobilizes the body during stressful situations (flight or flight)
- Parasympatheic - responsible for aquisition and storage of resources, predominates when the body is at rest.