fundamentals Of The Nervous System Flashcards
Integration
Interpretation of sensory output
Central nervous system
CNS. brain, spinal cord. Integration and communication.
Peripheral nervous system
PNS. Outside CNS. Spinal nerves and cranial nerves. Carries message to and from spinal cord and brain.
Sensory (afferent) division
Conveys message to the CNS from sensory receptors all over the body
Motor/efferent division
Transmits impulses from the CNS to effector organs (muscles and glands). Activates muscles to contract/glands secrete
Somatic nervous system
Composed of somatic nerve fibers (axons). Conduct impulses from CNS to skeletal muscles. Voluntary control of muscles.
Autonomic nervous system
Visceral motor nerve fibers. Regulates nerve fibers, cardiac muscle, and glands. Involuntary.
Sympathetic
Prepares for emergency. Fight or flight response.
Parasympathetic
Rest and digest.
Neuroglia
Supporting cells. Segregate and insulate neurons. Guide young neurons. Promote health and growth of neurons.
Neurons
Excitable cells that transmit electrical signals
Cell body
Contains nucleus and nucleolus. 1+ processes project from of, centrioles, axon hillock, most are found in CNS where they’re protected by the bony structures.
Dendrite
Short, tapering, branched processes. Main input regions of the neuron. Large surface area for signals. Conveys message toward cell body.
Axon
Each neuron has a single axon. Slender processes from the hillock. Generate and transmit actin potentials away from cell body to axon terminal
Myelin sheath
Shear around most long axons. Protects the axon, electrically insulate fibers from one another, increase speed of nerve impulse transmission
