Ch 8-12 Flashcards
(148 cards)
2 ways the divisions of the nervous system can be classified by
Location Type of tissue supplied by the nerve cells in the division
2 neural structures the central nervous system (CNS) consists of
Brain Spinal cord
4 neural structures the peripheral nervous system (PNS) made up of
12 pairs of cranial nerves 31 pairs of spinal nerves Autonomic nerves Ganglia
2 neurons the PNS consists ofA
Afferent neurons Efferent neurons
Neurons that conduct impulses from peripheral receptors to the CNS
Afferent (sensory) neurons
Neurons that conduct impulses away from the CNS to the peripheral effectors
Efferent (motor) neurons
Supplies the striated skeletal muscles
Somatic nervous system (SNS)
Supplies smooth muscle, cardiac muscle, and glandular epithelial tissue
Autonomic nervous system (ANS)
Basic unit of the nervous system Consists of a cell body and two types of long, threadlike extensions
Neuron Nerve cell
Fatty covering that insulate the axons and increase the rate of transmission of nervous impulses
Myelin sheath
Deterioration of the fatty myelin sheath
Demyelination
The impulse conduction route to and from the CNS in involuntary reactions Basic ones consists of an afferent/sensory neuron, which conducts impulses to the CNS from the periphery; an an efferent/motor neuron which conducts impulses from the CNS to peripheral effectors (muscles or glandular tissue)
Reflex arc
Junction where impulses pass from one neuron to another Transmission here is a chemical reaction in which the termini of the axon release a neurotransmitter substance that produces an electrical impulse in the dendrites of the next axon; once the neurotransmitter has accomplished its task, its activity rapidly terminates so that subsequent impulses pass along this same route
Synapse
Largest part of the brain that consists of two cerebral hemispheres
Cerebrum
Elevations the surface of the cerebrum is highly convoluted with
Gyri
Shallow grooves the surface of the cerebrum is highly convoluted with
Sulci
Deeper grooves in the cerebrum that divide each cerebral hemisphere into lobes
Fissures
Outer portion of the cerebrum consists of a thin layer of gray matter where the nerve cell bodies are concentrated Responsible for receiving sensory information from all parts of the body and for triggering impulses that govern all motor activity Just posterior to the central sulcus, there are specialized areas to receive and precisely localize sensory information from the PNS
Cerebral cortex
Mass of white matter that connects the two cerebral hemispheres These extensive bundles of nerve fibers lie in the midline just above the roofs of the lateral ventricles
Corpus callosum
A few gray islands of gray matter deep within the white matter Help control position and automatic movements and consist of the caudate nuclei, the globus pallidus, and the putamen
Basal ganglia
3 parts of the brainstem (from top down) between the cerebrum and spinal cord
Midbrain Pons Medulla
Performs sensory, motor, and reflex functions, and contains the nuclei of the 12 cranial nerves and the vital centers controlling cardiac, vasomotor, and respiratory function
Brainstem
Responsible for such nonvital reflexes as vomiting, coughing, sneezing, hiccuping, and swallowing
Medulla
Second largest part of the brain located just below the posterior portion of the cerebrum that is composes of two large lateral masses: the hemispheres and a central section (vermis) Acts with the cerebral cortex to produce skilled movements by coordinating the activities of groups of muscles Coordinates skeletal muscles used in maintaining equilibrium and posture by functioning below the level of consciousness to make movements smooth rather than jerky, steady rather than trembling, and efficient and coordinated rather than ineffective and awkward
Cerebellum