Chapter 7- Neurons Flashcards
Integrates and coordinates the body’s activities, CNS/PNS
Nervous system
Excitable cells that generate and transmit messages
Neurons (nerve cells)
Provide structural support, growth factors, and insulating sheaths around axons, 10:1
Neuroglial cells (glial cells)
Sensory, motor, interneurons
Types of neurons
Carry info toward the CNS from sensory receptors
Sensory neurons
Carry information away from CNS to affector (muscle or gland)
Motor neurons
Found only in brain and spinal cord, integrate and interpret sensory signals, account for 99% of neurons
Interneurons
Receive signals from other cells, carry info toward the cell body of a neuron
Dendrites
Carries info away from the cell body to either another neuron or an effector
Axon
Contains nucleus and other organelles, functions to maintain the neuron
Cell body
Provides electrical insulation that increases the rate of conduction of a nerve impulse
Myelin sheath
An electrochemical signal involving sodium and potassium ions that cods the cell membrane through ion channels
Nerve impulse or action potential
A disease in which the myelin sheath in the brain and spinal cord are progressively destroyed
Multiple sclerosis
Han a neuron is not conducting a nerve impulse
Resting potential
Minimum charge that causes the sodium gates to open
Threshold
