Nervous System Flashcards
Neuron
Basic functional unit.
Transmits messages/signals via electrical impulses.
Releases chemicals/neurotransmitters (into other neurons, muscles & glands) over short distances (effects are short lived)
Central Nervous System (CNS)
Brain & Spinal Cord.
Process incoming information & initiates a response.
Peripheral Nervous System (PNS)
Cranial nerves, spinal nerves (any nerves outside brain and spinal cord).
2 subdivisions: somatic & autonomic
Meninges
Specialized membrane that covers brain / spinal cord to protect them.
Cerebrospinal Fluid (CSF)
Mechanically and chemically protects the brain and spinal cord.
Sensory Nerves
Carry sensory input from environment to brain & spinal cord.
Motor Nerves
Carry motor impulses from the brain & spinal cord to muscles & glands.
Somatic Nervous System
Sensory neurons that send sensory information from sensory receptors of skeletal muscle, skin, special senses (taste, smell, sight, hearing & equilibrium) to the CNS and motor neurons that control skeletal muscle.
Mixed Nerves
Combination of both sensory & motor.
Autonomic Nervous System
Monitors and regulates changes in the body’s internal environment (changes are not under voluntary control). Processes include contractions of the stomach & other digestive organs, heartrate, contractions of blood vessels to control pressure & flow.
2 subdivisions: sympathetic & parasympathetic
Sympathetic Nervous System
Controls functions that speed up heart rate, increase energy usage during emergencies or stress.
Parasympathetic Nervous System
Reduces heart rate, decreases overall energy usage when body is returning to normal after an emergency or stress.
